MEDIUM
CVE-2021-40985
CWE-125Published: November 3, 2021· Updated: Jun 17, 2026
5.5
CVSS v3.1
Official Description
A stack-based buffer under-read in htmldoc before 1.9.12, allows attackers to cause a denial of service via a crafted BMP image to image_load_bmp.
Technical Analysis
CVE-2021-40985 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 5.5.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.None
User InteractionRequired
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Affected Vendors & Products
Debian1 product(s)
debian linux
htmldoc_project1 product(s)
htmldoc
Source: NVD CPE · 2 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (6)
→
https://github.com/michaelrsweet/htmldoc/commit/f12b9666e582a8e7b70f11b28e5ffc49ad625d43Patch · Third Party Advisory
→
https://github.com/michaelrsweet/htmldoc/issues/444Exploit · Issue Tracking · Patch · Third Party Advisory
→
https://lists.debian.org/debian-lts-announce/2022/02/msg00022.htmlMailing List · Third Party Advisory
→
https://github.com/michaelrsweet/htmldoc/commit/f12b9666e582a8e7b70f11b28e5ffc49ad625d43Patch · Third Party Advisory
→
https://github.com/michaelrsweet/htmldoc/issues/444Exploit · Issue Tracking · Patch · Third Party Advisory
→
https://lists.debian.org/debian-lts-announce/2022/02/msg00022.htmlMailing List · Third Party Advisory
Quick Facts
CVE IDCVE-2021-40985
CVSS Score5.5 / 10
SeverityMEDIUM
WeaknessCWE-125
CISA KEVNo
Affected2 vendor(s)
PublishedNov 3, 2021
Related CVEs (CWE-125)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-40985 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.