CVE-2025-55753: Apache HTTP Server: mod_md (ACME), unintended retry intervals

Published Dec 4, 2025
·
Updated

802.1X. An authentication issue was addressed with improved state management.

Other sources

Accounts. An authorization issue was addressed with improved state management.

Apple

Admin Framework. A path handling issue was addressed with improved validation.

Apple

An integer overflow in the case of failed ACME certificate renewal leads, after a number of failures (~30 days in default configurations), to the backoff timer becoming 0. Attempts to renew the certificate then are repeated without delays until it succeeds.

Launchpad

Apache HTTP Server: modmd (ACME), unintended retry intervals

Microsoft

apache. This is a vulnerability in open source code and Apple Software is among the affected projects. The CVE-ID was assigned by a third party. Learn more about the issue and CVE-ID at cve.org.

Apple

Credit

Rosyna Keller(Totally Not Malicious Software), CVE-2025-55753, CVE-2025-58098, CVE-2025-59775, CVE-2025-65082, CVE-2025-66200, Johnny Franks (zeroxjf), an anonymous researcher, Mickey Jin@@patch1t, Justin Cohen(Google), Jex Amro, Amy (amys.website), Cristian Dinca (icmd.tech), @@cloudlldb, Hossein Lotfi@@hosselot(TrendAI Zero Day Initiative), YingQi Shi@@Mas0nShi(DBAppSecurity's WeBin lab), Etienne Charron (Renault), Victoria Martini (Renault), Andreas Jaegersberger & Ro Achterberg(Nosebeard Labs), CVE-2025-14524, 风沐云烟@@binary_fmyy, Minghao Lin@@Y1nKoc, DARKNAVY@@DarkNavyOrg, Kirin@@Pwnrin, Zhongcheng Li(IES Red Team), CVE-2025-64505, Gor Aleksanyan(BoB 0xB6), Dhiyanesh Selvaraj@@redroot97(BoB 0xB6), 이동하 (Lee Dong Ha(BoB 0xB6), Jian Lee@@speedyfriend433, hari shanmugam, Johnny Franks@@zeroxjf, Sreejith Krishnan R, Himanshu Bharti@@Xpl0itme(Khatima), Chunyu Song(NorthSea), Rodolphe Brunetti@@eisw0lf(Lupus Nova), Matej Moravec@@MacejkoMoravec, Csaba Fitzl@@theevilbit(Iru), Dawuge(Shuffle Team), Hunan University, Kun Peeks@@SwayZGl1tZyyy, Gyujeong Jin at Team.0xb6@@G1uN4sh, wdszzml, Atuin Automated Vulnerability Discovery Engine, Alex Radocea, Christian Kohlschütter, Dave G., @@pixiepointsec, Caspian Tarafdar, Andrew Becker, Héloïse Gollier, Mathy Vanhoef (KU Leuven), Ryan Dowd@@_rdowd, Koh M. Nakagawa@@tsunek0h(FFRI Security Inc), Talal Haj Bakry(Mysk Inc), Tommy Mysk@@mysk_co(Mysk Inc), Zhongquan Li@@Guluisacat, Asaf Cohen, XiguaSec, Ye Zhang(Baidu Security), Ryan Dowd@@_rdowd(Iru), Joseph Ravichandran@@0xjprx(MIT CSAIL), Yuebin Sun@@yuebinsun2020(SecuRing), an anonymous researcher(SecuRing), Nathaniel Oh@@calysteon(SecuRing), Kirin@@Pwnrin(SecuRing), Wojciech Regula(SecuRing), Joshua Jewett@@JoshJewett33, Ilya Andr (andrd3v)(Voynich Group), Ilias Morad (A2nkF)(Voynich Group), Duy Trần@@khanhduytran0, @@hugeBlack, Gergely Kalman@@gergely_kalman, Andrei Dodu, Morris Richman@@morrisinlife, Luke Roberts@@rookuu, Pedro Tôrres@@t0rr3sp3dr0, webb, Thomas Espach, @@hamayanhamayan, Yeonghyeon Choi, Daniel Rhea, Söhnke Benedikt Fischedick (Tripton), Emrovsky & Switch3301, Yevhen Pervushyn, Minse Kim, Narcis Oliveras Fontàs, Nathaniel Oh@@calysteon, Hongze Wu(Ant Group Infrastructure Security Team), Shuaike Dong(Ant Group Infrastructure Security Team), greenbynox, Arni Hardarson, Gongyu Ma@@Mezone0

Affected Software

8 affected componentsFixes available
Apache HTTP Server>2.4.30<=2.4.66
Apache HTTP Server>=2.4.30<2.4.66
Microsoft cbl2 httpd 2.4.65-1
Microsoft azl3 httpd 2.4.65-1
Apple macOS Sequoia<15.7.5
15.7.5
Apple macOS Sonoma<14.8.5
14.8.5
Apple macOS Tahoe<26.4
26.4
debian/apache2<=2.4.62-1~deb11u1
2.4.67-1~deb11u12.4.67-1~deb12u22.4.67-1~deb13u22.4.67-1

Event History

Dec 5, 2025
CVE Published
via MITRE·10:12 AM
Data Sourced
via MITRE·10:12 AM
DescriptionWeakness
Data Sourced
via Red Hat·11:01 AM
DescriptionSeverityAffected Software
Data Sourced
via NVD·11:15 AM
DescriptionSeverityWeaknessAffected Software
Dec 11, 2025
Data Sourced
via Microsoft·01:02 AM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·01:02 AM
Affected Software
Updated
via Microsoft·01:02 AM
DescriptionSeverity
Mar 24, 2026
Data Sourced
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
DescriptionWeakness
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
Affected Software
May 28, 2026
Data Sourced
via Ubuntu·06:16 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·06:17 PM
DescriptionAffected Software
Data Sourced
via Launchpad·06:17 PM
Description

Parent advisories

This vulnerability appears in the following advisories.

Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2025-55753?

CVE-2025-55753 is classified as a moderate severity vulnerability due to the potential for repeated certificate renewal attempts without delays.

2

How do I fix CVE-2025-55753?

To fix CVE-2025-55753, you should upgrade your Apache HTTP Server to a version higher than 2.4.66.

3

What products are affected by CVE-2025-55753?

CVE-2025-55753 affects Apache HTTP Server versions between 2.4.30 and 2.4.66.

4

What is the impact of CVE-2025-55753 on my server?

The impact of CVE-2025-55753 can lead to excessive load and potential downtime due to unregulated certificate renewal attempts.

5

How can I determine if I am vulnerable to CVE-2025-55753?

You can determine vulnerability to CVE-2025-55753 by checking your Apache HTTP Server version and ensuring it is above 2.4.66.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203