Cyber Resilience

CVE-2026-25479

Litestar ≤ 2.20.0

Public PoC
Published
09 February 2026
Modified
17 February 2026
Patch / advisory
View advisory
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS Score 0.0032 24th percentile
Risk Priority 50 floored blend · peak EPSS

Summary

CVE-2026-25479 is a medium-severity Incorrect Regular Expression (CWE-185) vulnerability in Litestar Litestar. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked at the 24th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. Prior to 2.20.0, in litestar.middleware.allowed_hosts, allowlist entries are compiled into regex patterns in a way that allows regex metacharacters to retain special meaning (e.g., . matches any character). This enables a…

more

bypass where an attacker supplies a host that matches the regex but is not the intended literal hostname. This vulnerability is fixed in 2.20.0.

CWE(s)
CWE-185

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1566 Phishing Initial Access
Adversaries may send phishing messages to gain access to victim systems.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-25480Same product: Litestar Litestar
CVE-2024-52581Same product: Litestar Litestar
CVE-2026-25478Same product: Litestar Litestar
CVE-2026-33418Shared CWE-185
CVE-2024-52289Shared CWE-185
CVE-2026-25542Shared CWE-185
CVE-2025-20139Shared CWE-185
CVE-2026-27895Shared CWE-185
CVE-2026-4296Shared CWE-185
CVE-2026-24398Shared CWE-185

Affected Assets

litestar
litestar
≤ 2.20.0

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover regex that fails to match or compare data as intended.

SA-15 Development Process, Standards, and Tools partial match

Requiring documented development standards and tools reduces the chance that incorrect regular expressions are written into validation or filtering logic.

SA-3 System Development Life Cycle partial match

An SDLC that incorporates security can embed reviews or tooling that catch malformed regular expressions before deployment.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require correct regex design, testing, and review to avoid improper matching.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development can detect regex-related flaws before release.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle includes validation of input-handling constructs such as regex.

A.8.26 Application security requirements partial match
prevents

Application security requirements can mandate correct regex design and testing.

A.8.28 Secure coding partial match
prevents

Secure coding standards directly address proper construction and review of regular expressions.

References