CVE-2025-14822: mattermost Inefficient Algorithmic Complexity
CVSS: 6.5v3.1MediumAnalyzed
AliasesGHSA-9r42-rhw3-2222GO-2026-4325
Published 16-01-2026Last modified 16-01-2026
Vulnerability summary
CVE-2025-14822 is a medium (CVSS 6.5) Inefficient Algorithmic Complexity vulnerability in mattermost. EPSS estimates a 0.35% chance of exploitation in the next 30 days, higher than 27.1% of scored vulnerabilities.
CVSS score
6.5/10
010
Medium · v3.1 (NVD)EPSS score
0.35%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 2 · Related 2Timeline
- 16-01-2026PublishedVulnerability first disclosed.
- 16-01-2026Last modifiedVulnerability information updated.
Description
Mattermost versions 10.11.x <= 10.11.8 fail to validate input size before processing hashtags which allows an authenticated attacker to exhaust CPU resources via a single HTTP request containing a post with thousands space-separated tokens
CVSS metrics
3 scores · 3 sources · 1 versionMedium 6.5Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HSources3 sources · 3.1–6.5
- CVE.orgCNA3.1LowCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:LDiffers
- OSV · GoEcosystem advisory · calculated3.1LowCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:LDiffers
EPSS trend
Probability
0.35%
Chance of exploitation in the next 30 days
Percentile
27%
Versus all other CVEs
30-day change
0.00 pp
From 0.35% on 21-09-2026
21-09-202621-10-2026
EPSS score0.35%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-407Inefficient Algorithmic ComplexityAn algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.
- CWE-770Allocation of Resources Without Limits or ThrottlingThe product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
Affected systems
Mattermost2 products
- mattermost≥ 10.11.0, ≤ 10.11.8
- mattermost_server≥ 10.11.0, < 10.11.9
Github.com/mattermost1 product
- mattermost-server≥ 10.11.0, < 10.11.9 | ≥ 11.0.0, < 11.2.0 | ≥ 11.0.1+incompatible, < 11.2.0+incompatible
2 vendors · 3 products
