CVE-2026-73556

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Source
https://cve.org/CVERecord?id=CVE-2026-73556
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-73556.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-73556
Aliases
  • GHSA-48jh-3gj7-fg8v
Published
2026-08-13T14:56:52.569Z
Modified
2026-08-16T03:31:00.692996663Z
Severity
  • 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L CVSS Calculator
Summary
vLLM: ReDoS via structured_outputs.regex in the lm-format-enforcer backend (no compile timeout) — missed sibling of CVE-2026-55574
Details

vLLM is an inference and serving engine for large language models. Prior to 0.26.0, the structuredoutputs.regex parameter in vllm/v1/structuredoutput/backendlmformatenforcer.py is passed to lmformatenforcer.RegexParser without compileregexwithtimeout or validation in validatestructuredoutputrequestlmformatenforcer, allowing an unauthenticated /v1/completions request against the lm-format-enforcer backend to consume a CPU core and stall the structured-output engine path with a catastrophic regular expression. This issue is fixed in version 0.26.0.

Database specific 
{
    "cwe_ids": [
        "CWE-1333",
        "CWE-400"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73556.json",
    "cna_assigner": "GitHub_M"
}
References

Affected packages

Git / github.com/vllm-project/vllm

Affected ranges

Type
GIT
Repo
https://github.com/vllm-project/vllm
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
c9a788eedc412acceaa5112e0d44624b49841577
Fixed
ffd46bfab2128bb84146050e98b51a617c6575ab
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "0.26.0"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

Affected versions

Other
submission
v0.*
v0.1.0
v0.1.1
v0.1.2
v0.1.3
v0.1.4
v0.1.5
v0.1.6
v0.1.7
v0.10.0
v0.10.0rc1
v0.10.0rc2
v0.10.1rc1
v0.10.2rc1
v0.10.2rc2
v0.11.0rc1
v0.11.1
v0.11.1rc0
v0.11.1rc1
v0.11.1rc2
v0.11.1rc3
v0.11.1rc4
v0.11.1rc5
v0.11.1rc6
v0.13.0rc1
v0.14.0rc0
v0.14.0rc1
v0.15.0rc1
v0.15.2rc0
v0.16.0rc0
v0.16.0rc1
v0.17.0rc0
v0.17.1rc0
v0.17.2rc0
v0.18.0rc0
v0.18.1rc0
v0.18.2rc0
v0.19.1rc0
v0.19.2rc0
v0.2.0
v0.2.1
v0.2.2
v0.2.3
v0.2.4
v0.2.5
v0.2.6
v0.2.7
v0.20.1rc0
v0.20.2rc0
v0.21.1rc0
v0.22.1rc0
v0.23.1rc0
v0.25.0
v0.26.0rc1
v0.3.0
v0.3.1
v0.3.2
v0.3.3
v0.4.0
v0.4.0.post1
v0.4.1
v0.4.2
v0.4.3
v0.5.0
v0.5.0.post1
v0.5.1
v0.5.2
v0.5.3
v0.5.3.post1
v0.5.4
v0.5.5
v0.6.0
v0.6.1
v0.6.1.post1
v0.6.1.post2
v0.6.2
v0.6.3
v0.6.3.post1
v0.6.4
v0.6.4.post1
v0.6.5
v0.6.6
v0.6.6.post1
v0.7.0
v0.7.1
v0.7.2
v0.7.3
v0.8.0rc1
v0.8.0rc2
v0.8.1
v0.8.2
v0.8.3rc1
v0.8.4
v0.9.0
v0.9.1
v0.9.1rc1
v0.9.1rc2
v0.9.2rc1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-73556.json"