Recent efforts have demonstrated the strong capabilities of Multimodal Large Reasoning Models (MLRMs) in geographic reasoning. By jointly analyzing subtle visual cues, these models can infer the locations of photos, thus enabling doxing even by non-expert adversaries. Existing defense methods struggle to balance the shareability of photos with effective protection, and often fail to sufficiently disrupt the implicit geo-evidence chains embedded in scene semantics. To this end, we propose GeoEdit, an adversarial de-evidencing framework for silent geoprivacy protection via image editing. Specifically, we apply minimal edits to high-risk evidence anchors in the image, thereby disrupting the underlying spatial reasoning chains while preserving overall scene semantics. We identify these anchors by combining structured knowledge with adversarially discovered geographic cues. To further navigate the large editing action space, we adopt a learnable policy to iteratively refine editing decisions, distilling successful trajectories into transferable natural-language insights for consistent and efficient editing. Evaluated on LifePhotoBench, GeoEdit achieves strong protection against 6 mainstream MLRMs, outperforming visual perturbation baselines by over 0.59 in image fidelity.
Figures & tables
Figure 1. Comparison of social media sharing scenarios. The landmark check-in (a) exemplifies intentional location sharing. Conversely, the daily life photo (b) inadvertently leaks sensitive location data via implicit geo-evidence, resulting in non-consensual exposure and severe doxing risks.
Figure 2. Comparison of geoprivacy protection mechanisms. (a) The unprotected image. (b) Image Obfuscation hides sensitive areas but ruins the visual experience. (c) Visual Perturbation tricks visual encoders to protect geoprivacy, but its adversarial nature is often lost during unpredictable image processing and causes noticeable artifacts. (d) Geo-Evidence Editing (Ours) blocks the localization reasoning chain to defend against both MLRMs and human analysis while keeping visual appeal.
Figure 3. Overall architecture of GeoEdit. ❶ De-Evidencing Image Editing: A policy π explicitly reasons and acts within a ReAct loop, invoking the core tools Trisk , Tedit , and Teval to identify evidence, generate semantic edits, and verify protection quality. ❷ Self-Evolution via Insight Distillation: A test-time optimization mechanism that constructs group-relative joint reward signals from rollout trajectories, distilling them into natural-language protection insights ( K ) to guide future edits.
Evidence Source
Specific Features
Continuous Geo-Features
Similarity Mean, Similarity Variance
Discrete Geo-Features
Scene Complexity, Landmark Level, Text Value
Off-Image Features
Task Attractiveness, Geo-Hint
Image Quality
Weather, Focal Length, View Angle, Clarity
Table 1. The geolocation evidence schema ( Cheng et al., 2026 ) .
Figure 4. Overview of Self-Evolution via Geoprivacy Protection Insight Distillation. By contrasting successful and unsuccessful editing trajectories, GeoEdit distills a group relative advantage into a shared Insight Buffer ( K ).
Method
Fid. ( ↑ )
GPT-5.1 Acc@Km ( ↓ )
Claude-4.5-Sonnet Acc@Km ( ↓ )
Claude-3.7-Sonnet Acc@Km ( ↓ )
1km
25km
200km
750km
2500km
1km
25km
200km
750km
2500km
1km
25km
200km
750km
2500km
Unprotected
1.000
29.6
61.9
71.8
80.3
83.8
26.5
55.4
64.2
77.1
81.5
27.2
56.3
65.8
78.4
82.2
M-Attack
0.344
10.5
23.8
36.2
54.7
76.5
9.2
21.4
33.8
51.7
74.2
11.1
24.8
35.6
53.4
75.7
GeoShield
0.267
3.1
6.8
15.2
31.8
46.2
2.5
5.1
13.8
27.4
49.8
2.8
5.5
14.5
26.3
48.7
Vanilla Edit
0.893
18.3
36.8
49.0
70.0
81.4
16.5
33.2
45.2
66.4
79.8
17.1
34.5
46.8
67.5
80.5
GeoEdit (Ours)
0.944
2.6
5.7
14.9
30.5
53.8
2.1
4.2
13.0
28.6
51.3
2.3
4.8
13.9
29.9
52.5
Table 2. Experiment results of baseline comparisons on geoprivacy protection effectiveness. Geolocation prediction accuracy (%) is reported across different granularities. The best and second-best results are highlighted in bold and underlined, respectively.
Figure 5. Visualization of different protected images. GeoEdit achieves silent protection while preserving naturalness.
Method
Gemini-2.5
GLM-4.6V
Human 1
Human 2
W-D-L (%)
Cap-Fid ↑
W-D-L (%)
Cap-Fid ↑
W-D-L (%)
W-D-L (%)
Overall
vs. Orig.
Overall
vs. Orig.
Unprotected (original image)
72.0-14.7-13.3
1.000
84.0-0.0-16.0
1.000
76.6-8.0-15.4
0.0-100.0-0.0
83.6-0.9-15.5
0.0-100.0-0.0
M-Attack
25.3- 25.3 -49.4
0.801
45.3 -0.0-54.7
0.865
4.4- 22.8 -72.8
0.0-0.0-100.0
15.6-2.6-81.8
0.0-0.0-100.0
GeoShield
10.7- 16.0 -73.3
0.798
16.0-0.0-84.0
0.849
5.3- 24.8 -69.9
0.0-0.0-100.0
11.0-2.4-86.6
0.0-0.0-100.0
Vanilla Edit
46.5 -3.5-50.0
0.862
33.1-0.0-66.9
0.845
55.0 -13.1-31.9
18.6 - 16.8 -64.6
58.1 - 2.8 -39.1
23.6 -1.6-74.8
Table 3. Results of visual utility evaluation. W-D-L (%) is the percentage of Wins, Draws, and Losses for the images under each corresponding setting in blind pairwise A/B tests. Cap-Fid is MLRM’s caption fidelity of the protected images.
Setting
Fid. ↑
MDE (km) ↑
Gemini-2.5
GLM-4.6V
GPT-5.1
Claude-4.5
GeoEdit
0.944
5240.8
5821.3
3645.9
6836.3
w/o Trisk
0.915
2453.6
2847.2
1954.8
3158.4
w/o Tedit
0.931
3582.4
4251.6
2849.5
4526.8
w/o Teval
0.898
1627.5
1853.8
1482.2
2084.6
Vanilla Edit
0.893
1354.2
1428.5
1215.6
1583.4
Table 4. Ablation results for GeoEdit on geoprivacy protection effectiveness and fidelity on LifePhotoBench.
Figure 6. Impact of Protection Insight on GeoEdit. We report the average performance of all edited image attempts and corresponding ReAct steps per trajectory at each insight buffer size during self-evolution.
Example
Editing Insight
Detail of Insight
Subtractive Micro-Feature Removal
For non-landmark scenes, prioritize subtractive micro-feature removal (e.g., erasing botanical markers, scattered debris) over additive effects to avoid creating new regional archetypes.
Cultural Marker Neutralization
Identify and replace culturally distinctive elements with contextually plausible but globally generic alternatives to create semantic ambiguity while preserving the overall scene narrative.
Semantic Simplification
Replace distinctive features with neutral, context-appropriate surfaces rather than generating new complex patterns, while maintaining natural weathering and texture noise, specifically optimizing for indoor scenes to maximize ambiguity while preserving naturalness.
Structural Naturalization
Replace specific man-made structures with generic natural elements via subtle substitution to break database links and hierarchical narratives while maintaining visual plausibility.
Table 5. Interpretability analysis of key protection insights distilled via self-evolution.
Figure 7. Defense Performance (MDE ↑ , km) under DOX-Prompt and DOX-CoT Probing across two MLRMs.
Method
Original
JPEG ( Q=50 )
Blur ( σ=10 )
GeoShield
6836.3
5235.9
7198.0
GeoEdit (Ours)
5240.8
5118.1
5349.8
Table 6. Robustness of GeoEdit under transformations (Geolocation model: Gemini-2.5). Evaluated by Median Distance Error.
Privacy protection in vision-language models limits sensitive information exposure while preserving useful image understanding and multimodal reasoning.
Multimodal large reasoning models (MLRMs) have demonstrated remarkable capabilities in complex visual understanding. However, this very power introduces a critical yet underexplored privacy threat: adversaries can exploit MLRMs to precisely infer users' geographic locations from casually shared photographs, by performing structured reasoning over subtle visual cues such as architectural styles, vegetation, and lighting conditions. In this work, we present a systematic study of MLRM-driven geolocation privacy leakage. We first reveal that refusal-based safeguards are critically insufficient, as carefully crafted jailbreak prompts can raise model response rates to 100%. We further identify that existing defenses, which inject imperceptible perturbations into shared images, suffer from structural limitations intrinsic to their pixel-space optimization, resulting in degraded black-box transferability and pronounced visual artifacts. Motivated by these findings, we propose a diffusion-based framework that provides targeted, proactive defense against geolocation privacy leakage. By injecting perturbations into the latent space of a diffusion model during reverse sampling, our method operates directly on high-level semantic representations, thereby resolving the effectiveness-utility bottlenecks by construction. We further ground our optimization with GeoCLIP, a model explicitly aligned with GPS coordinates, as a surrogate to pinpoint and disrupt the geographic signals that MLRMs exploit for location inference. This targeted semantic disruption yields significantly stronger black-box transferability while preserving perceptual image quality, offering a seamless integration on social media platforms. Code is available at https://github.com/RachelWolowitz/Hiding_in_plain_sight.
Yining Wang, Xi Li, Mi Zhang +4
Fudan University · East China University of Science and Technology · Shanghai University of Electric Power
The rapid advancement of large vision language models (LVLMs) has made geolocation inference from images highly accurate and accessible. This poses serious privacy risks: a passive adversary with black-box LVLM access can infer a user's location from a single photo with no metadata. Existing protection methods rely almost exclusively on adversarial perturbation, which introduces perceptible visual artifacts and utility degradation. We identify the visual-geolocation asymmetry: geolocation-decisive clues, such as street signs, tend to be visually peripheral but dominate location inference. Exploiting this asymmetry, we propose GeoCloak, an agentic framework for semantics-preserving geolocation privacy protection. It acts as a clue-aware planner that analyzes each image to identify geolocation-relevant clues, dispatches targeted semantic edits to directly suppress peripheral clues, and autonomously configures adversarial perturbation to further suppress residual geolocation features, all under iterative utility-aware feedback. We evaluate GeoCloak on four diverse datasets spanning 108 countries and 576 cities against five LVLMs and three inference methods. GeoCloak reduces overall city-level accuracy from 41.2% to 9.9%, approximately half of the best-performing baseline, while achieving substantially superior utility preservation both qualitatively and quantitatively. We hope this work takes a meaningful step toward practical, semantics-preserving geolocation privacy protection, giving users greater control over the location information inadvertently embedded in their shared images.
Yixin Wu, Mingjie Li, Yun Shen +2
The Hong Kong University of Science and Technology (Guangzhou) · The Hong Kong University of Science and Technology · CISPA Helmholtz Center for Information Security +1
Retrieval-based image geolocalization has emerged as a powerful technique for determining the location of a query image by matching it against a large, geotagged database. The success of deep learning based approaches has raised concerns regarding privacy and safety. A way to protect users from geolocalization is to design adversarial attacks for such methods. In this paper, we introduce RoadTrip Attack (RTA), a novel and highly effective targeted adversarial attack for geolocalization. RTA conceptualizes the adversarial process as finding an optimal distractor journey to a specific, attacker-chosen location. It employs a beam search algorithm to iteratively construct a sequence of incorrect geographic locations that form a path to the target. At each step, the attack generates subtle perturbations to the query image, guiding the geolocalization model toward the next location in this deceptive path. We show that our method is also strong in black-box settings, obtaining highly transferable attacks with less perceptible image artifacts.
Niccolò Niccoli, Federico Becattini, Lorenzo Seidenari
University of Florence, Florence, Italy · University of Siena, Siena, Italy