Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
☕
☕ Maven
Not in CISA KEV
HIGH severity

CVE-2026-41850 — spring-expression

HIGH

CVE-2026-41850 is a high-severity (CVSS 7.5) CWE-407 vulnerability in org.springframework:spring-expression. A fix is available for org.springframework:spring-expression — see the affected versions and patch details below.

Spring Framework Algorithmic Denial of Service via SpEL Expressions

Published
Jun 9, 2026
Updated
Sep 10, 2026
Affected
4 pkgs
Patched
2 / 4
Exploits
None indexed
Exploitation data as of Sep 26, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

  • CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
  • CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-41850.

EPSS Exploitation Probability

via FIRST.org ↗
0.5%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs37th percentile — riskier than 37% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

How urgent is this, really

CVE-2026-41850 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.

Where this sits among everything scored

Of 379,145 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.

Real-World Exposure

4 pkgs affected
☕org.springframework:spring-expression☕org.springframework:spring-expression☕org.springframework:spring-expression☕org.springframework:spring-expression

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Applications that evaluate user-supplied Spring Expression Language (SpEL) expressions are vulnerable to an Algorithmic Denial of Service (DoS). By providing a specially crafted expression, an attacker can trigger excessive resource consumption during evaluation, leading to application degradation or unavailability.

Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.

Affected Packages

4 total 2 fixed
EcosystemPackageVulnerable rangeFix
☕Mavenorg.springframework:spring-expression≥ 7.0.0&&< 7.0.87.0.8org.springframework:spring-expression:7.0.8
☕Mavenorg.springframework:spring-expression≥ 6.2.0&&< 6.2.196.2.19org.springframework:spring-expression:6.2.19
☕Mavenorg.springframework:spring-expression≥ 6.1.0No fix
☕Mavenorg.springframework:spring-expressionall versionsNo fix

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.springframework:spring-expression, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update org.springframework:spring-expression to 7.0.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41850 is resolved across your whole dependency graph.

  3. Workarounds

    Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-41850 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2026-41850. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

A flaw was found in Spring Framework. Applications that evaluate user-supplied Spring Expression Language (SpEL) expressions are vulnerable to an Algorithmic Denial of Service (DoS). By providing a specially crafted expression, an attacker can trigger excessive resource consumption during evaluation, leading to…

Workaround published by Red Hat
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Source: Red Hat security advisory for CVE-2026-41850 (CC BY 4.0)

Frequently Asked Questions

Applications that evaluate user-supplied Spring Expression Language (SpEL) expressions are vulnerable to an Algorithmic Denial of Service (DoS). By providing a specially crafted expression, an attacker can trigger excessive resource consumption during evaluation, leading to application degradation or unavailability. Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.
O3 Security · Impact-Aware SCA

Is CVE-2026-41850 in your dependencies?

O3 Security finds CVE-2026-41850 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

CVE-2026-41850: spring DoS (High 7.5) | O3 Security