# CVE-2026-115721: Apache Vysper: Unbounded allocation

Status: published. Published: 2026-10-26. Updated: 2026-11-02.

**UNSUPPORTED WHEN ASSIGNED**  Unbounded allocation in XML parsing in Apache Vysper; all versions, may lead to an out of memory condition.




This issue affects all versions of Apache Vysper. Apache Vysper is an XMPP (Jabber) server library.




As this project is retired, we do not plan to release a version that fixes this issue. Users are recommended to find an alternative.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Apache Software Foundation / Apache Vysper (org.apache.vysper:vysper): ≥ 0; ≤ * (affected, maven). Source: CNA: apache

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: apache

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: NVD: security@apache.org

- CISA KEV: No listing in collected sources

- EPSS: 0.47% as of 2026-11-02; percentile 40.96%

- SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-770

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://mina.apache.org/vysper-project/ (CNA: apache)

- https://lists.apache.org/thread.html/d0bx15hjcs69gktk9tt25vgvk121c9vm (CNA: apache; vendor-advisory)

- http://www.openwall.com/lists/oss-security/2026/10/23/20 (ADP: CVE)

- https://lists.apache.org/thread.html/d0bx15hjcs69gktk9tt25vgvk121c9vm (security@apache.org)

- https://mina.apache.org/vysper-project/ (security@apache.org)

- http://www.openwall.com/lists/oss-security/2026/10/23/20 (af854a3a-2127-422b-91ae-364da2661108)

## Provenance

- CNA: apache: https://www.cve.org/CVERecord?id=CVE-2026-115721; retrieved 2026-11-02; source updated 2026-11-02

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-115721; retrieved 2026-11-03; source updated 2026-11-02

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-115721; retrieved 2026-11-02; source updated Not reported

Revision: f006fea28abd22ccbef852c4208cf2c8fcc16eee2dc5078f06e23dade0044ff9

Canonical: https://y2.dev/cve/CVE-2026-115721

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