ThorVG: Heap buffer overflow (OOB write) in bundled jpgd JPEG decoder
Affects ThorVG 1.1.1 and earlier, including main before the fix, when it decodes a crafted JPEG with a repeated scan component. Fixed in 1.1.2.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 1.1.2
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. ThorVG version 1.1.1 or earlier (also main before the fix) A crafted JPEG with a repeated component in the SOS scan header, such as a grayscale image listing its one component several times The JPEG is decoded by ThorVG, either as a plain image or embedded in a Lottie file
- Last modified
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 19/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
ThorVG, a vector graphics engine, has a heap buffer overflow in its bundled jpgd JPEG decoder, caused by duplicate component selectors in a crafted JPEG's scan header. A remote attacker who gets a user to open a crafted JPEG, including one embedded in Lottie content, can corrupt memory and crash the process, with no login required.
Read the original description
Thor Vector Graphics (ThorVG) is a production-ready vector graphics engine. Prior to 1.1.2, the bundled jpgd JPEG decoder accepts duplicate component selectors in an SOS scan header, causing each duplicate to increase m_blocks_per_mcu without checking the buffers sized from the frame components. A crafted grayscale JPEG can repeat its component in the SOS header, causing decode paths in src/loaders/jpg/tvgJpgd.cpp to write beyond heap buffers sized for one component. The issue is reachable through direct JPEG decoding and through JPEG images embedded in Lottie content, and confirmed impact is memory corruption followed by a process crash. This issue is fixed in version 1.1.2.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure12/25Specific setups only, reachable over the network without a login
- Reach?/20Unknown. No tracked technology or package matched
- Severity7.4/10CVSS 7.4
- No patch0/5No signal
What would change the score
- Would score about 69 if added to CISA KEV
- Would score about 64 if CISA's SSVC rates exploitation active
What to do
Check whether your setup matches what the bug needs.
ThorVG version 1.1.1 or earlier (also main before the fix) A crafted JPEG with a repeated component in the SOS scan header, such as a grayscale image listing its one component several times The JPEG is decoded by ThorVG, either as a plain image or embedded in a Lottie fileUpgrade to a fixed version: 1.1.2.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- thorvg thorvg
fixed in 1.1.2
Evidence 4
- Advisory
- Repository
- Repository
- Repository
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-123367
Is CVE-2026-123367 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
The bundled jpgd JPEG decoder can write past the end of a heap buffer when a JPEG lists the same component several times in its SOS scan header. At minimum this crashes the process, causing denial of service, and further escalation toward code execution may be possible.Source: github.com
Which versions are affected by CVE-2026-123367?
thorvg: before 1.1.2.Source: cve.now feed data
Am I affected, and how do I check?
Versions 1.1.0, 1.1.1 and main before the fix are listed as affected. Any image ThorVG decodes can trigger it, including a plain .jpg or a JPEG embedded in a Lottie file, so check the ThorVG version your build uses against 1.1.2.Source: github.com
How do I fix CVE-2026-123367?
Upgrade ThorVG to 1.1.2 or later, which contains the fix.Source: github.com