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TI-2026-00601 Aliases CVE-2026-0819GHSA-3cr6-hpf3-2hmg

Stack buffer overflow in PKCS7 SignedData encoding with custom signed attributes

Priority LOW 12CWE-121Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

A stack buffer overflow vulnerability exists in wolfSSL's PKCS7 SignedData encoding functionality. In wc_PKCS7_BuildSignedAttributes(), when adding custom signed attributes, the code passes an incorrect capacity value (esd->signedAttribsCount) to EncodeAttributes() instead of the remaining available space in the fixed-size signedAttribs[7] array. When an application sets pkcs7->signedAttribsSz to a value greater than MAX_SIGNED_ATTRIBS_SZ (default 7) minus the number of default attributes already added, EncodeAttributes() writes beyond the array bounds, causing stack memory corruption. In WOLFSSL_SMALL_STACK builds, this becomes heap corruption. Exploitation requires an application that allows untrusted input to control the signedAttribs array size when calling wc_PKCS7_EncodeSignedData() or related signing functions.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00105 1st percentileScored 2026-11-07
Fix Fixed wolfSSL (wolfSSL): 5.9.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
wolfSSLwolfSSL5.5.0 to before 5.9.05.9.0Patch availableCNA
  • wolfSSL VendorwolfSSL Affected 5.5.0 to before 5.9.0 Fixed in 5.9.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*5.5.0 to before 5.9.0VulnerablewolfSSL
  • cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:* Versions 5.5.0 to before 5.9.0 Vulnerable ·wolfSSL

Remediation

  • Fix · CNA wolfSSL (wolfSSL) Fixed in 5.9.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    wolfSSL 5.9.0

    7 records Highest priority Priority MEDIUM 1 MEDIUM, 6 LOW

    Other records, highest priority first

    • TI-2026-03058 Buffer overflow in CRL number parsing in wolfSSLPriority MEDIUM 40
    • TI-2026-03057 wolfSSL: out-of-bounds read (DoS) in ALPN parsing due to incomplete validationPriority LOW 39
    • TI-2026-03086 Non-constant time multiplication subroutine __muldi3 on RISC-V RV32IPriority LOW 11
    Show all 7 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-0819
  2. 2026-10-03 Alias added: GHSA-3cr6-hpf3-2hmg

References

Patch 1

  • TI-2024-00830 SEGV and out of bounds memory read from malicious packet CVSS 3.1CRITICAL 9.1
  • TI-2022-18557 In wolfSSL before 5.5.1, malicious clients can cause a buffer overflow during a TLS 1.3… CVSS 3.1HIGH 7.5
  • TI-2025-10943 Potential DoS Vulnerability through Multiple KeyShareEntry with Same Group in TLS 1.3 ClientHello CVSS 4.0MEDIUM 6.3
  • TI-2017-09737 wolfSSL Bleichenbacher/ROBOT CVSS 3.0HIGH 7.5
  • TI-2019-08902 wolfSSL 4.0.0 has a Buffer Overflow in DoPreSharedKeys in tls13.c when a current identity… CVSS 3.1CRITICAL 9.8
  • TI-2017-02021 Improper certificate validation in wolfSSL CVSS 3.1CRITICAL 9.8
See all 150 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences