How severe is CVE-2025-3677?

CVE-2025-3677 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2025-3677 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2025-3677?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-3677 have an EU (EUVD) identifier?

Yes. CVE-2025-3677 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11794.

When was CVE-2025-3677 published?

CVE-2025-3677 was published on 2025-04-16 and last updated on 2026-06-17.

CVE-2025-3677

CVE-2025-3677 is a medium-severity vulnerability with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 4.3
CVSS v4: 4.8
EPSS exploit prediction: 0% (8th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-11794
Weakness: CWE-20
Published: 2025-04-16
Last modified: 2026-06-17

Description

A vulnerability classified as critical was found in lm-sys fastchat up to 0.2.36. This vulnerability affects the function split_files/apply_delta_low_cpu_mem of the file fastchat/model/apply_delta.py. The manipulation leads to deserialization. An attack has to be approached locally.

Frequently asked questions

What is CVE-2025-3677?: A vulnerability classified as critical was found in lm-sys fastchat up to 0.2.36. This vulnerability affects the function split_files/apply_delta_low_cpu_mem of the file fastchat/model/apply_delta.py. The manipulation leads to deserialization. An attack has to be approached locally.
How severe is CVE-2025-3677?: CVE-2025-3677 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2025-3677 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-3677?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-3677 have an EU (EUVD) identifier?: Yes. CVE-2025-3677 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11794.
When was CVE-2025-3677 published?: CVE-2025-3677 was published on 2025-04-16 and last updated on 2026-06-17.

References

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