Security readout for executives and security teams
Plain-English summary
Exiv2 versions before 0.27.4 can mishandle a specially crafted image when writing metadata. The main business risk is disruption of tools or services that process untrusted images with Exiv2 metadata-write operations. The vendor fixed the issue in 0.27.4.
Executive priority
Treat as routine patching unless Exiv2 writes metadata on untrusted images in production. Prioritize internet-facing upload pipelines, media processing workers, and batch systems where crashes could interrupt service.
Technical view
CVE-2021-29463 is a CWE-125 out-of-bounds read in Exiv2::WebPImage::doWriteMetadata affecting Exiv2 0.27.3 and earlier. It is triggered during metadata writing, not routine metadata reading. Sources describe potential denial of service through a crash after user interaction with a crafted image.
Likely exposure
Exposure is most likely in image-processing workflows that use Exiv2 CLI or library versions below 0.27.4 to write metadata to untrusted files. Systems only reading metadata appear less exposed based on the advisory.
Exploitation context
No source in the bundle reports active exploitation, and the CVE is not listed as KEV. Exploitation requires tricking a victim or workflow into running Exiv2 metadata-writing behavior on a crafted image file.
Researcher notes
The advisory narrows triggering to write-metadata behavior in WebP handling and notes this is less common than reading metadata. Evidence supports fixed version 0.27.4, but the bundle does not provide proof of active exploitation or broader product impact.
Mitigation direction
- Upgrade Exiv2 to version 0.27.4 or later.
- Apply fixed distribution packages from Fedora, Gentoo, or other relevant vendors.
- Limit Exiv2 metadata-writing on untrusted image uploads until upgraded.
- Review vendor guidance for downstream package-specific remediation.
Validation and detection
- Inventory Exiv2 CLI and linked library versions across hosts and containers.
- Confirm no deployed version is 0.27.3 or earlier.
- Identify workflows that write metadata to user-supplied images.
- Verify patched packages are installed where Exiv2 is used operationally.
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-125: Exact CWE lookup
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Open ATT&CK lookupCVE-2021-29463 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
- Low
- CVSS
- 3.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
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 vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N1.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
3.3LowVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/Exiv2/exiv2/security/advisories/GHSA-5p8g-9xf3-gfrrCVE reference
- https://github.com/Exiv2/exiv2/commit/783b3a6ff15ed6f82a8f8e6c8a6f3b84a9b04d4bCVE reference
- FEDORA-2021-0b27f220bdCVE reference · vendor-advisory
- FEDORA-2021-dde4d7d47eCVE reference · vendor-advisory
- GLSA-202312-06CVE reference · vendor-advisory
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.
Out-of-bounds Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.