CVE-2026-23918: Apache HTTP Server: http2: double free and possible RCE on early reset

Published May 4, 2026
·
Updated

Accounts Framework. This issue was addressed with improved data protection.

Other sources

Accounts. A parsing issue in the handling of directory paths was addressed with improved path validation.

— Apple

Accounts. An access issue was addressed with additional sandbox restrictions.

— Apple

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

— Apple

afpfs. A buffer overflow was addressed with improved bounds checking.

— Apple

Apache HTTP Server: http2: double free and possible RCE on early reset

— Microsoft

Credit

Adam Franke(CyStack), Ashish Kunwar(CyStack), Trung Nguyen@@everping(CyStack), Rosyna Keller(Totally Not Malicious Software), Dave G., Bartlomiej Dmitruk(striga), Stanislaw Strzalkowski(isec), Narendra Singh@@_3P1C, Peter Malone, Rahul Raj, Pinak Oza, Robert Mindo, 章鱼哥.com@@aipyaipy, Chris Bailey - Short Circuit, N.M.Praveen Nawarathne@@zblockrat, Stuart Wallace, Vladislav Shevchenko (Positive Technologies), an anonymous researcher, tamdao, Franco Belman at Blackwing Intelligence, Dun, Rishabh Jain (rjcyber)(cyberplanet), Irvin Wang, Nicolas Rabrenovic, impost0r (ret2plt), David Ige - Beryllium Security, lokerxx(Economics), Narendra Singh@@_3P1C(Economics), Lyutoon(Economics), Jordy Zomer@@pwningsystems(Economics), Richard Zana(Economics), Aswin Kumar Gokulakannan(Economics), George Stergiopoulos(Economics), InfoSec lab(Economics), Athens University(Economics), Business, Greece, 이재영, Pavan Nallamothu, Jared Reyes, John Lussier, Seonung Park, ALTV!ST (altvi.st/), David Strnadel, YingQi Shi@@Mas0nShi(DBAppSecurity's WeBin lab), Richard Zana, Nathaniel Oh@@calysteon, Anton Pakhunov, Rodolphe BRUNETTI@@eisw0lf(Lupus Nova), Daniel Febrero, Daniel Williams, Arni Hardarson (Neonix Security), Gergely Kalman@@gergely_kalman, Anonymous(TrendAI Zero Day Initiative), ret2happy, Mathis Mansière, Csaba Fitzl@@theevilbit(Iru), Rajdip Dey Sarkar, James Duffy@@0x4A616D657344, Kraken Cryptocurrency Exchange(Nosebeard Labs), Andreas Jaegersberger & Ro Achterberg(Nosebeard Labs), Matthew Schneider, Dallas Dubs(Nosebeard Labs), Aaron Grattafiori - NVIDIA AI Red Team(Nosebeard Labs), XBreach.ai(Nosebeard Labs), Yongyue WANG AKA Brian.W(OKX security), Roman Zabicki(Nosebeard Labs), Katika Mohaseen(Nosebeard Labs), an anonymous researcher(Nosebeard Labs), CVE-2026-3784, CVE-2026-3783, HvxyZLF, Lance Cain - Offensive Security Engineer, SpecterOps Inc., Tommy DeVoss@@thedawgyg(Braze Security Team), Mahmoud Abdelmoniem(DBAppSecurity's WeBin lab), Kujtim Kryeziu(DBAppSecurity's WeBin lab), 이재영(Nosebeard Labs), Ilya Andr (andrd3v)(Nosebeard Labs), beist, Hyunwoo Kim@@v4bel, Gil Portnoy & Henry, Anthony Laou Hine Tsuei@@anarcheuz, Ayaan Ahmad, erdene-och Byambabayar, Niels Hofmans, Manuel Fernandez (Stackhopper Security), Ilya Andr (andrd3v)(Positive Technologies), Stanislav Jelezoglo, Somair Ansar(Calif), Josh Maine(Calif), Johnny Franks@@0xjohnny, hxr1, Alexandre Soleiman, Alexander Tarasikov, Ruslan Dautov, Redon Gashi, Atul R V & Ashmit Sharma, Hcamael, 章鱼哥 （aipyaipy.com）@@aipy, Aswin Kumar Gokulakannan, Surya Narayan Kushwaha, Cem Onat Karagun, Alfredo Pesoli@@__rev(Bynar), Tristan Madani@@TristanInSec(Talence Security), Surya Kushwaha, Michael DePlante@@izobashi(TrendAI Zero Day Initiative), Arni Hardarson, Jonathan Alush-Aben, 진규정 (Gyujeong Jin, @@G1uN4sh, PETOWORKS의 Bugeun Choi@@Bugeun, Geonha Lee@@leegn4a, Igor Ushakov, Billy Jheng Bing Jhong(STAR Labs SG Pte), Pan Zhenpeng@@Peterpan0927(STAR Labs SG Pte), Ashish Kunwar, Hiroki Imai (LAC Co., Ltd.), Ryan Hileman via Xint Code (xint.io), Ashish Kunwar(MurphySec), f0r(MurphySec), Feng Xue(ThreatBook), XGPT(ThreatBook), Mahmoud Abdelmoniem, Wang Yu, Lyutoon, DARKNAVY@@DarkNavyOrg, Fábio Luís@@scanpt, Adam Doupé(ASU SEFCOM), Pasquale Scola(STAR Labs SG Pte), Gor Aleksanyan, impost0r (ret2plt)(Appknox), Ruslan Dautov(Appknox), Aleksandr Tarasikov(Appknox), jay(Appknox), Dhiyanesh Selvaraj@@redroot97(Appknox), Vinay Kumar Rasala (Xplo8E)(Appknox), Lyutoon(STAR Labs SG Pte), DongJun Kim (smlijun) with UIUC(STAR Labs SG Pte), Hwiwon Lee (hwiwonl) with UIUC(STAR Labs SG Pte), Jongseong Kim (nevul37) with UIUC(STAR Labs SG Pte), Younggi Park (grill66) with UIUC(STAR Labs SG Pte), Peter Malone(STAR Labs SG Pte), an anonymous researcher(STAR Labs SG Pte), Hari Shanmugam (The Hxr1)(STAR Labs SG Pte), Marco Grassi, Daniele Castronovo, Michal Kosiorek, Ruslan Dautov(Baidu Security), 재영 정(Baidu Security), (Rao Ali Nawaz)@@rootxran(Baidu Security), Chanwit Muenprakoddee (ChemIndy)(Baidu Security), an anonymous researcher(Baidu Security), Ye Zhang@@VAR10CK(Baidu Security), Franco Belman at Blackwing Intelligence(Calif), Christian Figueroa(Calif), Johnny Franks@@0xjohnny(Calif), Ashmit Sharma & Atul RV(Calif), Peter Malone(Calif), Muhamad Syaiful(Calif), Muneeb Amin Bhat(Calif), Dhiyanesh Selvaraj@@redroot97(Calif), Ali Marzouq(Calif), Bountyy Oy - Mihalis Haatainen(Calif), Huy Nguyen@@34306(Calif), Eddy Tsalolikhin, beist(ASU SEFCOM), Dun(STAR Labs SG Pte), Asjid Kalam@@odinshell, Abhijeet Singh (linkedin.com/in/abhiunix/), Omar Cerrito, Wang Yu(STAR Labs SG Pte), Ji'an Zhou, Mingxuan Yang, Ye Zhang, Jian Zhou, Calif Research, Ernesto Martínez García, Lukas Gerlach, YingMuo@@YingMuo(DEVCORE Research Team), Tristan Rousseau, Dun(DARKNAVY), deepsec@@DarkNavyOrg(DARKNAVY), CVE-2026-4424, Amy (amys.website), He Wei (ギカク)(aipyaipy), 章鱼哥@@aipy(aipyaipy), Jex Amro, Daisuke Hatakeyama Research)@@SYZD, Richard Zana(Nosebeard Labs), yk lin@@pixiepointsec, stratan@@5tratan, wh0am1i, Robert Tran, Mickey Jin@@patch1t, Koh M. Nakagawa@@tsunek0h(FFRI Security Inc), Matej Moravec@@MacejkoMoravec, Aethel-Systems(Chongqing Telecom), Chanwit Muenprakoddee (ChemIndy)(Chongqing Telecom), 九宫格(Chongqing Telecom), Narcis Oliveras Fontàs, Sindre Sorhus, Francisco Knabe, Zachary Neal(Stripe), Hcamael(Stripe), 章鱼哥 (aipyaipy.com)@@aipy(Stripe), JC Alvarado(Stripe), Jacob Hazak, @@pixiepointsec, Ilya Andr (andrd3v), Nik Tsytsarkin, Asaf Cohen, Junming C.(Chapoly1305), wdszzml, Atuin Automated Vulnerability Discovery Engine, Bob Gendler(the National Institute of Standards), Technology, RedRays Security Team, Vivek Dhar, ASI (RM) in Border Security Force, FTR HQ BSF Kashmir, He Wei (ギカク)(Cisco Talos), Claudio Bozzato(Cisco Talos), Francesco Benvenuto(Cisco Talos), Kitten Food, Calif.io in collaboration with Claude, Anthropic Research, Tien-Chih Lin(CyCraft Technology), Tien-Chih Lin, Bruce Dang(Calif), Kwak Kiyong, Song Nuri, Kagami Rosylight(Mozilla), Luke Francis(Z), Francisco Alonso@@revskills(Z), Shubham Chaskar(Z), Jiyong Yang@@Sy2n0(Z), 杉山 壮太(Z), lattice(Z), Behzad Najjarpour Jabbari@@_G4ru_(Z), Junyeong Lee(Z), Mooth.ai(Z), OGINOME Tomohito(Z), Using GLM(Z), Gia Bui@@yabeow(Calif), Milad Nasr, Nicholas Carlini with Claude, Anthropic, Heiko Kiesel(SEEMOO), TU Darmstadt, Brian Carpenter, OGINOME Tomohito, Shaheen Fazim, 이재영(Appknox), Peter Malone(cyberplanet), Nicolas Rabrenovic(cyberplanet), Irvin Wang(cyberplanet), CVE-2025-14017, CVE-2025-14819, Jonathan Bar Or@@yo_yo_yo_jbo, Stanislav Jelezoglo(Positive Technologies), Gandalf4a(PKU), Dhiyanesh Selvaraj@@redroot97, hxr1(STAR Labs SG Pte), Hiroki Imai (LAC Co.(STAR Labs SG Pte), Ltd.)(STAR Labs SG Pte), Mahmoud Abdelmoniem(ThreatBook), Hyunwoo Kim@@v4bel(ThreatBook), Vladislav Shevchenko (Positive Technologies)(STAR Labs SG Pte), Kirin@@Pwnrin(Fudan University), LFY@@secsys(Fudan University), Prathamesh Walunj@@attahasa, Atul R V, Dan Raviv, Chanwit Muenprakoddee (ChemIndy), Aethel-Systems, Aaron Grattafiori - NVIDIA AI Red Team, Pyrophoria, Estifanos Megersa, Ahmed Uddin, silo, wdszzml(Bynar), Atuin Automated Vulnerability Discovery Engine(Bynar)

Affected Software

6 affected componentsFixes available
Apache HTTP Server=2.4.66
Apache HTTP Server=2.4.66
Apple macOS Sequoia<15.7.8
15.7.8
Apple macOS Sonoma<14.8.8
14.8.8
Apple macOS Tahoe<26.6
26.6
Microsoft azl3 httpd 2.4.66-1<2.4.67-1
2.4.67-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 2.4.67-1
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 26.6
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 15.7.8
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 14.8.8
  5. Upgrade

    Upgrade Apache HTTP Server to a version that resolves this vulnerability.

    Fixed in 2.4.67
  6. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Patch CVE-2026-23918

Event History

May 4, 2026
CVE Published
via MITRE·02:44 PM
Data Sourced
via MITRE·02:44 PM
DescriptionWeakness
Data Sourced
via Red Hat·03:02 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·03:16 PM
DescriptionSeverityWeaknessAffected Software
May 7, 2026
Data Sourced
via Microsoft·08:11 AM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·08:11 AM
DescriptionSeverity
May 26, 2026
Exploit Published
via ExploitDB·12:00 AM
Known Exploited
07:02 PM
Jul 27, 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

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2026-23918?

CVE-2026-23918 is classified as a high-severity vulnerability due to the potential for remote code execution.

2

How do I fix CVE-2026-23918?

To resolve CVE-2026-23918, upgrade your Apache HTTP Server from version 2.4.66 to 2.4.67.

3

What impact does CVE-2026-23918 have on Apache HTTP Server?

CVE-2026-23918 can lead to a double free vulnerability, which may allow unauthorized remote code execution.

4

Which versions of Apache HTTP Server are affected by CVE-2026-23918?

CVE-2026-23918 specifically affects Apache HTTP Server version 2.4.66.

5

Is CVE-2026-23918 specific to a certain protocol?

Yes, CVE-2026-23918 is related to the HTTP/2 protocol within Apache HTTP Server.

Company

Resources

Contact

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