Security readout for executives and security teams
Plain-English summary
A crafted image can make Exiv2 hang when a user or automated process modifies metadata and deletes IPTC data. The result is denial of service, not data theft or code execution. Exposure is mainly image-processing workflows that run vulnerable Exiv2 versions on untrusted files.
Executive priority
Treat as a moderate operational reliability risk. Prioritize patching internet-facing or user-upload image workflows, but this is not sourced as remote code execution or known exploited activity.
Technical view
CVE-2021-37623 is a CWE-835 infinite loop in Exiv2 v0.27.4 and earlier. Sources state it is triggered while modifying crafted image metadata, specifically when deleting IPTC data with an extra option. The issue is fixed in v0.27.5.
Likely exposure
Organizations are exposed if they use Exiv2 command-line tooling or the C++ library at version 0.27.4 or earlier, especially in user-submitted image handling or metadata-cleaning pipelines.
Exploitation context
The source bundle does not show active exploitation or KEV listing. Exploitation requires a victim or workflow to process a crafted image with the vulnerable IPTC deletion operation, causing availability impact.
Researcher notes
Key constraints matter: the advisory narrows triggering to crafted images during metadata modification, specifically IPTC deletion. Validate real exposure by mapping Exiv2 invocation paths rather than assuming all image reads are exploitable.
Mitigation direction
- Upgrade Exiv2 to v0.27.5 or a vendor-patched package.
- Identify automated image metadata workflows that accept untrusted files.
- Avoid vulnerable IPTC deletion operations until patched.
- Run image processing in isolated workers with resource limits.
- Check Fedora, Gentoo, or relevant distro advisories for fixed packages.
Validation and detection
- Confirm installed Exiv2 versions are later than 0.27.4.
- Review applications linking against the Exiv2 C++ library.
- Search jobs and scripts for Exiv2 metadata deletion usage.
- Verify vendor security updates were applied on managed systems.
- Monitor image-processing services for hangs or worker exhaustion.
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
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ATT&CK lookup starting points
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CWE-835: Exact CWE lookup
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Open ATT&CK lookupCVE-2021-37623 mapping review
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Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
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:N/A:H1.83.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/Exiv2/exiv2/security/advisories/GHSA-mvc4-g5pv-4qqqCVE reference
- https://github.com/Exiv2/exiv2/pull/1790CVE reference
- FEDORA-2021-399f869889CVE reference · vendor-advisory
- FEDORA-2021-cbaef8e2d5CVE 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.
Loop with Unreachable Exit Condition ('Infinite Loop')
Loop with Unreachable Exit Condition ('Infinite Loop') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.