CVE-2026-10043: MosaicML Composer · Deserialization of Untrusted Data
Affects MosaicML ComposerSource CVE Database V5
Not known to be exploited · CVSS 7.8 High.
Data as of 6 Nov 2026, 23:24 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 46% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 24 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 6 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| MosaicMLComposer | Affected
| Fixed in– |
PyPImosaicml/composerpkg:pypi/mosaicml/composerOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until an official fix is available, users should avoid opening untrusted checkpoint files or visiting untrusted web pages that could trigger the vulnerability. Monitoring vendor communications for updates is recommended.
Description
CVE-2026-10043 is a high-severity vulnerability in MosaicML Composer version 0.32.1 involving deserialization of untrusted data. The flaw occurs during the parsing of checkpoints, where insufficient validation allows remote attackers to execute arbitrary code. Exploitation requires user interaction, such as visiting a malicious page or opening a malicious file. This vulnerability can lead to full compromise of the affected process.