Security readout for executives and security teams
Plain-English summary
Accusoft ImageGear 19.10 can mishandle certain crafted JPEG-JFIF lossless Huffman images, causing heap memory corruption. If a business service uses this library to process untrusted images, an attacker-controlled file could threaten confidentiality, integrity, and availability.
Executive priority
Treat this as urgent for any exposed image-processing workflow using ImageGear 19.10. The CVSS score is critical, but urgency depends on whether untrusted files reach the vulnerable parser and whether a vendor-supported fix is available.
Technical view
CVE-2021-21946 covers two heap-based buffer overflows in ImageGear 19.10's JPEG-JFIF lossless Huffman parser. The CVE states the overflow occurs when SOF3 precision is lower than 9. CVSS 3.0 is 9.8 with network, low-complexity, no-privilege, no-user-interaction scoring.
Likely exposure
Exposure is likely where Accusoft ImageGear 19.10 processes externally supplied JPEG-JFIF or image files, especially automated upload, conversion, scanning, or document-processing workflows. The source bundle names only ImageGear 19.10 as affected.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation evidence. The described attack path is a specially crafted file reaching the vulnerable image parser. No exploit code or weaponized procedure is needed to understand the exposure.
Researcher notes
The evidence identifies the vulnerable component, affected version, CWE-122, parser condition, and CVSS vector. It does not provide active exploitation proof, a KEV entry, or remediation details in the supplied bundle. Avoid expanding affected versions beyond ImageGear 19.10.
Mitigation direction
- Inventory systems and applications using Accusoft ImageGear 19.10.
- Check Accusoft guidance for fixed versions or supported remediation.
- Reduce or pause untrusted JPEG-JFIF processing until remediated.
- Isolate image-processing services from sensitive systems and data.
- Apply strict file intake controls where ImageGear remains exposed.
Validation and detection
- Confirm whether deployed applications include Accusoft ImageGear 19.10.
- Identify routes, APIs, or jobs that parse user-supplied image files.
- Review SBOMs, vendor manifests, and packaged dependencies for ImageGear.
- Verify remediation against Accusoft guidance when available.
- Check logs for crashes tied to image parsing workflows.
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
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CWE-122: Exact CWE lookup
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Open ATT&CK lookupCVE-2021-21946 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
- Critical
- CVSS
- 9.8 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
9.8CriticalVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://talosintelligence.com/vulnerability_reports/TALOS-2021-1375CVE reference · x_refsource_MISC
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.
Heap-based Buffer Overflow
Heap-based Buffer Overflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.