VulnerabilityDeferred

CVE-2025-55398

In UPER (Unaligned Packed Encoding Rules), asn1c-generated decoders fail to enforce INTEGER constraints when the bound is positive and exceeds 32 bits in length, potentially allowing incorrect or malicious input to be processed.

CRITICAL 9.8EPSS 0.37%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.37%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

An issue was discovered in mouse07410 asn1c thru 0.9.29 (2025-03-20) - a fork of vlm asn1c. In UPER (Unaligned Packed Encoding Rules), asn1c-generated decoders fail to enforce INTEGER constraints when the bound is positive and exceeds 32 bits in length, potentially allowing incorrect or malicious input to be processed.

CVSS 3.1: 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.37% probability · 30th percentile
CISA KEV: Not listed
Weakness: CWE-1284
Source: cve@mitre.org

References

https://github.com/mouse07410/asn1c/issues/222

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.