CVE-2026-6878 json
ByteDance verl grader.py math_equal sandbox
published 6mo ago modified 16d ago also GHSA-h57c-v2v3-5v3v , PYSEC-2026-3402 , EUVD-2026-25146
- cvss
- 5.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 27%
- public exploits
- 0
- none known
Summary
A vulnerability was identified in ByteDance verl up to 0.7.0. Affected is the function math_equal of the file prime_math/grader.py. The manipulation leads to sandbox issue. It is possible to initiate the attack remotely. The complexity of an attack is rather high. The exploitability is told to be difficult. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6mo ago
Exploit prediction
0.33% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-11).
Exploits and checks
- github.com https://github.com/zast-ai/vulnerability-reports/blob/main/bytedance/verl_rce.md referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.3 | 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:P |
| CNA | 3.1 | 5.6 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R |
| CNA | 3.0 | 5.6 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R |
| CNA | 2.0 | 5.1 | AV:N/AC:H/Au:N/C:P/I:P/A:P/E:POC/RL:ND/RC:UR |
| CNA | 4.0 | 2.9 | 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:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| CNA | 3.1 | 5.6 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L |
| CNA | 2.0 | 5.1 | AV:N/AC:H/Au:N/C:P/I:P/A:P |
| GitHub | 3.1 | 5.6 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L |
| OSV | 3.1 | 5.6 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | verl | <=0.7.1 |
no fix listed |
Affected products
- ByteDance verl
Classification
References
-
github.com
/zast-ai/vulnerability-reports/blob/main/bytedance/verl_rce.md
exploit, web
-
vuldb.com
/vuln/359040
vdb-entry, technical-description, web
-
vuldb.com
/vuln/359040/cti
signature, permissions-required, web
-
vuldb.com
/submit/795257
third-party-advisory, web
-
nvd.nist.gov
/vuln/detail/CVE-2026-6878
advisory
-
github.com
/verl-project/verl
package
-
github.com
/verl-project/verl/blob/v0.7.1/verl/utils/reward_score/prime_math/grader.py
web
-
pypi.org
/project/verl
package
-
github.com
/advisories/GHSA-h57c-v2v3-5v3v
advisory
Sources
- CVE List CVE-2026-6878
- GitHub Advisory GHSA-h57c-v2v3-5v3v
- NVD CVE-2026-6878
- OSV PYSEC-2026-3402
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.