CVE-2026-18929 Resource Exhaustion in Carbone
Attackers can crash the application server by submitting malicious .docx files containing zip bombs, causing excessive memory consumption.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-18929?
CVE-2026-18929 is a medium-severity denial of service vulnerability in Carbone, published on 18 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Carbone is vulnerable to Denial of Service due to lack of protection against zip bombs when processing .docx files. The library uses yazl for zip decompression without validating entry sizes, allowing an attacker to supply a malicious .docx file containing a zip bomb that decompresses to a significantly larger size, causing excessive memory consumption and crashing the application server.
The issue was fixed in versions: 3.8.2, 4.26.3 and 5.4.4. The fix is available across all distribution types.
Weakness: CWE-409
Which versions are affected by CVE-2026-18929?
How do I fix CVE-2026-18929?
No fix has been published for CVE-2026-18929 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-18929 being exploited?
There is no known exploitation of CVE-2026-18929 in the wild and no public exploit code.
Sources
Also known as GHSA-g3fg-g325-xmh2.