CVE-2025-3777
Improper Input Validation in huggingface/transformers
Hugging Face Transformers versions up to 4.49.0 are affected by an improper input validation vulnerability in the image_utils.py file. The vulnerability arises from insecure URL validation using the startswith() method, which can be bypassed through URL username injection. This allows attackers to craft URLs that appear to be from YouTube but resolve to malicious domains, potentially leading to phishing attacks, malware distribution, or data exfiltration. The issue is fixed in version 4.52.1.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
3.5
Improper Input Validation in huggingface/transformers
Hugging Face Transformers versions up to 4.49.0 are affected by an improper input validation vulnerability in the image_utils.py file. The vulnerability arises from insecure URL validation using the startswith() method, which can be bypassed through URL username injection. This allows attackers to craft URLs that appear to be from YouTube but resolve to malicious domains, potentially leading to phishing attacks, malware distribution, or data exfiltration. The issue is fixed in version 4.52.1.
- Record
CVE-2025-3777- CVSS 3.0
- 3.5 Low
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
EUVDEUVD-2025-20211
3.5
Hugging Face Transformers versions up to 4.49.0 are affected by an improper input validation vulnerability in the image_utils.py file. The vulnerability arises from insecure URL validation using the startswith() method, which can be bypassed through URL username injection. This allows attackers to craft URLs that appear to be from YouTube but resolve to malicious domains, potentially leading to phishing attacks, malware distribution, or data exfiltration. The issue is fixed in version 4.52.1.
- Record
EUVD-2025-20211- CVSS 3.0
- 3.5 Low
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-phhr-52qp-3mj4
3.5
Transformers's Improper Input Validation vulnerability can be exploited through username injection
Hugging Face Transformers versions up to 4.49.0 are affected by an improper input validation vulnerability in the image_utils.py file. The vulnerability arises from insecure URL validation using the startswith() method, which can be bypassed through URL username injection. This allows attackers to craft URLs that appear to be from YouTube but resolve to malicious domains, potentially leading to phishing attacks, malware distribution, or data exfiltration. The issue is fixed in version 4.52.1.
- Record
GHSA-phhr-52qp-3mj4- CVSS 3.0
- 3.5 Low
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
NVD
3.5
Hugging Face Transformers versions up to 4.49.0 are affected by an improper input validation vulnerability in the image_utils.py file. The vulnerability arises from insecure URL validation using the startswith() method, which can be bypassed through URL username injection. This allows attackers to craft URLs that appear to be from YouTube but resolve to malicious domains, potentially leading to phishing attacks, malware distribution, or data exfiltration. The issue is fixed in version 4.52.1.
- Record
CVE-2025-3777- CVSS 3.0
- 3.5 Low
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
OSV
3.5
Improper Input Validation in huggingface/transformers
Hugging Face Transformers versions up to 4.49.0 are affected by an improper input validation vulnerability in the image_utils.py file. The vulnerability arises from insecure URL validation using the startswith() method, which can be bypassed through URL username injection. This allows attackers to craft URLs that appear to be from YouTube but resolve to malicious domains, potentially leading to phishing attacks, malware distribution, or data exfiltration. The issue is fixed in version 4.52.1.
- Record
CVE-2025-3777- CVSS 3.0
- 3.5 Low
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
OSVGHSA-phhr-52qp-3mj4
3.5
Transformers's Improper Input Validation vulnerability can be exploited through username injection
Hugging Face Transformers versions up to 4.49.0 are affected by an improper input validation vulnerability in the image_utils.py file. The vulnerability arises from insecure URL validation using the startswith() method, which can be bypassed through URL username injection. This allows attackers to craft URLs that appear to be from YouTube but resolve to malicious domains, potentially leading to phishing attacks, malware distribution, or data exfiltration. The issue is fixed in version 4.52.1.
- Record
GHSA-phhr-52qp-3mj4- CVSS 3.0
- 3.5 Low
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
OSVPYSEC-2026-1986
3.5
Transformers's Improper Input Validation vulnerability can be exploited through username injection
Hugging Face Transformers versions up to 4.49.0 are affected by an improper input validation vulnerability in the image_utils.py file. The vulnerability arises from insecure URL validation using the startswith() method, which can be bypassed through URL username injection. This allows attackers to craft URLs that appear to be from YouTube but resolve to malicious domains, potentially leading to phishing attacks, malware distribution, or data exfiltration. The issue is fixed in version 4.52.1.
- Record
PYSEC-2026-1986- CVSS 3.0
- 3.5 Low
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
transformersPyPI |
before 4.52.1 | 4.52.1 |
transformersPyPI |
before 4.52.1, plus listed versions 0.12.0.02.1.02.1.12.10.0 Show 45 moreShow less2.11.02.2.02.2.12.2.22.3.02.4.02.4.12.5.02.5.12.6.02.7.02.8.02.9.02.9.13.0.03.0.13.0.23.1.03.2.03.3.03.3.13.4.03.5.03.5.14.0.04.0.0rc14.0.14.1.04.1.14.10.04.10.14.10.24.10.34.11.04.11.14.11.24.11.34.12.04.12.14.12.24.12.34.12.44.12.54.13.04.14.0 |
4.52.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-3777 is a low vulnerability (CVSS 3.5) in Huggingface Huggingface/transformers, published July 7, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.41%, the 34th percentile. Fixed in transformers 4.52.1.
References
huntr.com/bounties/ccba0730-9248-4853-b7ff-5c20e6364f09
github.com/huggingface/transformers/commit/4dda5f71b35fb70cf602187eef84bb17a50b9082
nvd.nist.gov/vuln/detail/CVE-2025-3777
github.com/huggingface/transformers/blame/a7d2bbaaa8aac64f7c1ee8c1421cfe84b38359a4/src/transformers/image_utils.py
github.com/advisories/GHSA-phhr-52qp-3mj4
github.com/CVEProject/cvelistV5/tree/main/cves/2025/3xxx/CVE-2025-3777.json
github.com/huggingface/transformers
pypi.org/project/transformers
Left out here: 130 versions. The JSON record has them.