CVE-2026-6878: verl's math_equal() Vulnerable to Arbitrary Code Execution via Unsafe eval()
Affects verlSource GCVE Database
Public exploit available · CVSS 6.3 Medium.
Data as of 27 Oct 2026, 00:30 UTC
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 23 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
CVSS exploit maturity: proof of concept public
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), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| PyPIverl | 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
Users should avoid using affected versions (<=0.7.1) of verl until a fix is released. Monitor vendor channels for updates. Due to the high complexity and difficulty of exploitation, immediate urgent mitigation may not be required, but caution is advised given the availability of public exploit code.
Description
CVE-2026-6878 is a vulnerability in ByteDance verl up to version 0.7.1 affecting the math_equal function in prime_math/grader.py. The flaw involves unsafe use of eval(), leading to a sandbox escape that allows arbitrary code execution. The vulnerability can be exploited remotely but requires high attack complexity and is considered difficult to exploit. Public exploit code is available. The vendor has not responded to disclosure requests and no patch is currently available.
References
- nvd.nist.gov/vuln/detail/CVE-2026-6878 (opens in a new tab)
- github.com/verl-project/verl (opens in a new tab)
- github.com/verl-project/verl/blob/v0.7.1/verl/utils/reward_score/prime_math/grader.py (opens in a new tab)
- github.com/zast-ai/vulnerability-reports/blob/main/bytedance/verl_rce.md (opens in a new tab)
- vuldb.com/submit/795257 (opens in a new tab)
- vuldb.com/vuln/359040 (opens in a new tab)
- vuldb.com/vuln/359040/cti (opens in a new tab)