How severe is CVE-2025-63651?

CVE-2025-63651 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-63651 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-63651?

CVE-2025-63651 affects Monkey-project Monkey. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-63651?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-63651 have an EU (EUVD) identifier?

Yes. CVE-2025-63651 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-206528.

When was CVE-2025-63651 published?

CVE-2025-63651 was published on 2026-01-29 and last updated on 2026-06-17.

CVE-2025-63651

CVE-2025-63651 is a high-severity vulnerability in Monkey-project Monkey with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-206528
Weakness: CWE-416
Affected product: Monkey-project Monkey
Published: 2026-01-29
Last modified: 2026-06-17

Description

A use-after-free in the mk_string_char_search function (mk_core/mk_string.c) of monkey commit f37e984 allows attackers to cause a Denial of Service (DoS) via sending a crafted HTTP request to the server.

Frequently asked questions

What is CVE-2025-63651?: A use-after-free in the mk_string_char_search function (mk_core/mk_string.c) of monkey commit f37e984 allows attackers to cause a Denial of Service (DoS) via sending a crafted HTTP request to the server.
How severe is CVE-2025-63651?: CVE-2025-63651 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-63651 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-63651?: CVE-2025-63651 affects Monkey-project Monkey. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-63651?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-63651 have an EU (EUVD) identifier?: Yes. CVE-2025-63651 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-206528.
When was CVE-2025-63651 published?: CVE-2025-63651 was published on 2026-01-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:monkey-project:monkey:*:*:*:*:*:*:*:*

More vulnerabilities in Monkey-project Monkey

CVE-2013-2159 — Critical (CVSS 9.8): Monkey HTTP Daemon: broken user name authentication
CVE-2025-63658 — High (CVSS 7.5): A stack overflow in the mk_http_index_lookup function (mk_server/mk_http.c) of monkey commit f37e984 allows attackers…
CVE-2025-63657 — High (CVSS 7.5): An out-of-bounds read in the mk_mimetype_find function (mk_server/mk_mimetype.c) of monkey commit f37e984 allows…
CVE-2025-63656 — High (CVSS 7.5): An out-of-bounds read in the header_cmp function (mk_server/mk_http_parser.c) of monkey commit f37e984 allows attackers…
CVE-2025-63655 — High (CVSS 7.5): A NULL pointer dereference in the mk_http_range_parse function (mk_server/mk_http.c) of monkey commit f37e984 allows…
CVE-2025-63653 — High (CVSS 7.5): An out-of-bounds read in the mk_vhost_fdt_close function (mk_server/mk_vhost.c) of monkey commit f37e984 allows…

All CVEs affecting Monkey-project Monkey →

Other CWE-416 (Use After Free) vulnerabilities

CVE-2026-13782 — Critical (CVSS 10.0): Use after free in Browser in Google Chrome prior to 150.0.7871.47 allowed a remote attacker who had compromised the…
CVE-2026-4725 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 149…
CVE-2026-4688 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox…
CVE-2025-24085 — Critical (CVSS 10.0): A use after free issue was addressed with improved memory management. This issue is fixed in iOS 18.3 and iPadOS 18.3,…
CVE-2024-43102 — Critical (CVSS 10.0): Concurrent removals of certain anonymous shared memory mappings by using the UMTX_SHM_DESTROY sub-request of…
CVE-2021-32495 — Critical (CVSS 10.0): Radare2 has a use-after-free vulnerability in pyc parser's get_none_object function. Attacker can read freed memory…

Browse all CWE-416 (Use After Free) vulnerabilities →