Vulnerability · Published Sep 9, 2026 · Assigned by VulnCheck

CVE-2026-87822t-digest 3.1 through 3.3 Denial of Service via NaN Centroid Means in MergingDigest.fromBytes

High 7.5

In plain English

A high-severity security flaw in t-digest from tdunning. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.7%top 47.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

t-digest versions 3.1 through 3.3 fail to validate centroid means during deserialization in MergingDigest.fromBytes, allowing attackers to inject NaN values that bypass validation checks. Attackers can craft malicious serialized digests containing NaN centroids that degrade sorting performance from O(n log n) to O(n squared), causing severe processing delays during merge operations.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Ubuntu:22.04:LTS	t-digest	no fix listed	UBUNTU-CVE-2026-87822
Ubuntu:24.04:LTS	t-digest	no fix listed	UBUNTU-CVE-2026-87822
Ubuntu:26.04:LTS	t-digest	no fix listed	UBUNTU-CVE-2026-87822
Ubuntu:26.10	t-digest	no fix listed	UBUNTU-CVE-2026-87822

Affected products (as reported)

Vendor	Product	Versions
tdunning	t-digest	3.1 – through 3.3

Weakness: CWE-407 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

tdunning/t-digest issue #229 issue-tracking
fromBytes writing centroid means with no NaN check at the 3.3 release commit technical-description
stableQuickSort three-way partition that degrades on NaN at the 3.3 release commit technical-description
https://github.com/tdunning/t-digest product
VulnCheck Advisory: t-digest 3.1 through 3.3 Denial of Service via NaN Centroid Means in MergingDigest.fromBytes third-party-advisory