Security readout for executives and security teams
Plain-English summary
CVE-2021-42781 is a heap buffer overflow in OpenSC’s Oberthur PKCS#15 parsing code. The reported impact is that programs using the OpenSC library could crash. Sources do not provide CVSS scoring, active exploitation evidence, or affected downstream products beyond OpenSC.
Executive priority
Treat this as a targeted maintenance priority, not an emergency, unless OpenSC supports critical authentication workflows or exposed services in your environment.
Technical view
OpenSC before 0.22.0 has heap buffer overflow issues in pkcs15-oberthur.c, categorized as CWE-119. The referenced upstream commits and Gentoo/Debian advisories indicate security fixes exist, but the provided bundle does not describe exploitability beyond potential process crash.
Likely exposure
Exposure is most likely where OpenSC is installed or bundled for smart-card, PKCS#15, or certificate-token workflows, especially versions before 0.22.0 or unpatched distribution packages.
Exploitation context
The bundle marks CISA KEV as false and provides no cited evidence of active exploitation. The stated impact is potential crashes in programs using the library, not confirmed code execution.
Researcher notes
Useful follow-up is version and package provenance validation. The source bundle does not include CVSS, proof of exploitation, detailed attack prerequisites, or a confirmed impact beyond process crash.
Mitigation direction
- Upgrade OpenSC to 0.22.0 or a vendor-patched package.
- Apply relevant distribution security updates from Gentoo, Debian, or your platform vendor.
- Check vendor guidance if OpenSC is embedded in third-party software.
- Prioritize systems processing untrusted or externally supplied smart-card data.
Validation and detection
- Inventory hosts and applications with OpenSC installed or bundled.
- Confirm installed OpenSC versions or vendor package changelogs include the referenced fixes.
- Review smart-card authentication services for OpenSC dependency paths.
- Monitor crash reports from applications using OpenSC libraries.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-119: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-42781 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://bugzilla.redhat.com/show_bug.cgi?id=2016439CVE reference
- https://github.com/OpenSC/OpenSC/commit/17d8980cCVE reference
- https://github.com/OpenSC/OpenSC/commit/40c50a3aCVE reference
- https://github.com/OpenSC/OpenSC/commit/05648b06CVE reference
- https://github.com/OpenSC/OpenSC/commit/5d4daf6cCVE reference
- https://github.com/OpenSC/OpenSC/commit/cae5c71fCVE reference
- GLSA-202209-03CVE reference · vendor-advisory
- [debian-lts-announce] 20230621 [SECURITY] [DLA 3463-1] opensc security updateCVE reference · mailing-list
- https://lists.debian.org/debian-lts-announce/2024/12/msg00026.htmlCVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Restriction of Operations within the Bounds of a Memory Buffer
Improper Restriction of Operations within the Bounds of a Memory Buffer represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.