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Researchers report exploitation attempts against Brotli flaw

Part of the CVE-2026-111497 story · since 21 Oct

Developinglatest 1 hour ago19 articles7 outlets
21 Oct · SecurityOnline first25 Oct26 Oct27 OctNowThis article19th of 19
  • Wed 21 Oct, 17:54 UTC. SecurityOnline, first report. Node.js fixes Brotli flaw that could enable remote code execution. Cites a CVE in CISA KEV.
  • Fri 23 Oct, 08:35 UTC. The Hacker News, its first report on the story. Node.js Brotli flaw enables remote code execution in Linux arm64 builds. Cites a CVE in CISA KEV.
  • Sat 24 Oct, 11:00 UTC. The Hacker News. Brotli Flaw Enables Code Execution in Unpatched Node.js Builds. Cites a CVE in CISA KEV.
  • Sun 25 Oct, 08:30 UTC. The Hacker News. OpenAI Agents Expose VM Escapes and Sandbox Weaknesses. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 01:30 UTC. SecurityOnline. Brotli flaw expands Node2Shell risk across HTTP applications. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 03:19 UTC. SecurityOnline. Microsoft issues out of band .NET fixes for four flaws. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 11:00 UTC. SecurityWeek, its first report on the story. Brotli flaw triggers security updates across major software. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 13:00 UTC. SOCRadar, its first report on the story. Brotli flaw exposes Python packages to remote code execution. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 13:30 UTC. Infosecurity, its first report on the story. Microsoft patches critical .NET flaw that risks memory corruption. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 15:31 UTC. The Hacker News. Weekly recap tracks PHP and Node.js RCE flaws and supply chain attacks. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 18:30 UTC. The Hacker News. PHP releases rebuilt Windows packages to fix Brotli flaw. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 19:00 UTC. Rapid7, its first report on the story. Node.js Brotli flaw could expose memory or enable remote code execution. Cites a CVE in CISA KEV.
  • Tue 27 Oct, 02:00 UTC. SecurityOnline. Palo Alto confirms critical Brotli flaw affects PAN-OS. Cites a CVE in CISA KEV.
  • Tue 27 Oct, 20:01 UTC. CISA, its first report on the story. CISA adds exploited Google Brotli flaw to KEV catalogue. Cites a CVE in CISA KEV.
  • Tue 27 Oct, 23:00 UTC. SecurityOnline. Sweet Security offers free protection against HTTP2Shell. Cites a CVE in CISA KEV.
  • Wed 28 Oct, 01:00 UTC. SecurityOnline. CISA Adds Adobe Magento and Google Brotli Flaws to KEV Catalog. Cites a CVE in CISA KEV.
  • Wed 28 Oct, 08:00 UTC. SecurityOnline. Broadcom warns of critical VMware SDDC Manager flaw. Cites a CVE in CISA KEV.
  • Wed 28 Oct, 08:01 UTC. The Hacker News. CISA Adds Two Actively Exploited Flaws to KEV Catalog. Cites a CVE in CISA KEV.
  • Wed 28 Oct, 09:30 UTC. SecurityWeek. Researchers report exploitation attempts against Brotli flaw. Cites a CVE in CISA KEV. This article, 19th of 19.

The US Cybersecurity and Infrastructure Security Agency (CISA) has added the Brotli vulnerability known as Node2Shell (CVE-2026-111497), also referred to as HTTP2Shell and Broccoli2Shell, to its Known Exploited Vulnerabilities (KEV) catalog. The flaw is an out-of-bounds write in the Brotli decoder and affects Brotli versions 1.0.3 through 1.2.0. With specially crafted compressed data, an attacker could crash the target, expose memory contents, or potentially execute arbitrary code.

OpenAI researchers reported the flaw, and fixes were released by Node.js and Google on 21 October, with other maintainers—Microsoft, Bun, Envoy and Istio—also issuing patches. Palo Alto Networks is rolling out hotfixes for PAN-OS. CISA added CVE-2026-111497 to KEV on 27 October, and federal civilian agencies have been instructed to patch by 10 November.

Independent researchers and honeypot operators have observed exploitation attempts. Previdian, which monitors its own sensor network, logged a single exploitation attempt on 27 October from a US-based IP, with the firm describing the exploitation confidence as “confirmed” (acknowledging that confirmation does not guarantee success).

ELLIO, which tracks reconnaissance and mass exploitation, reported a malicious request targeting Node.js 24.22.0 on x86-64 on 26 October; its tests found the delivery matched public PoC code, but the final stage crafted by the attacker did not produce a shell across 50 tests. ELLIO notes the payload’s broken final stage suggests an early, perhaps unfinished, wild deployment, and warns that failed attempts can still crash services, potentially enabling DoS.

VMware patches are pending for CVE-2026-111497 in SDDC Manager and related products. Imperva has demonstrated code execution on an official Node.js image.

How the story developed

All 19 articles
Developinglatest 1 hour ago19 articles7 outlets

19 articles from 7 outlets since 21 Oct. Still developing; the latest report was 1 hour ago. This was the 19th report, 7 days after the first.

Now21 Oct2324252627First reportSecurityOnline · 21 Oct, 17:54This article19th of 19 · day 7CISA alert27 Oct, 20:01 · official
  • Wed 21 Oct, 17:54 UTC. SecurityOnline, first report. Node.js fixes Brotli flaw that could enable remote code execution. Cites a CVE in CISA KEV.
  • Fri 23 Oct, 08:35 UTC. The Hacker News, its first report on the story. Node.js Brotli flaw enables remote code execution in Linux arm64 builds. Cites a CVE in CISA KEV.
  • Sat 24 Oct, 11:00 UTC. The Hacker News. Brotli Flaw Enables Code Execution in Unpatched Node.js Builds. Cites a CVE in CISA KEV.
  • Sun 25 Oct, 08:30 UTC. The Hacker News. OpenAI Agents Expose VM Escapes and Sandbox Weaknesses. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 01:30 UTC. SecurityOnline. Brotli flaw expands Node2Shell risk across HTTP applications. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 03:19 UTC. SecurityOnline. Microsoft issues out of band .NET fixes for four flaws. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 11:00 UTC. SecurityWeek, its first report on the story. Brotli flaw triggers security updates across major software. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 13:00 UTC. SOCRadar, its first report on the story. Brotli flaw exposes Python packages to remote code execution. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 13:30 UTC. Infosecurity, its first report on the story. Microsoft patches critical .NET flaw that risks memory corruption. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 15:31 UTC. The Hacker News. Weekly recap tracks PHP and Node.js RCE flaws and supply chain attacks. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 18:30 UTC. The Hacker News. PHP releases rebuilt Windows packages to fix Brotli flaw. Cites a CVE in CISA KEV.
  • Mon 26 Oct, 19:00 UTC. Rapid7, its first report on the story. Node.js Brotli flaw could expose memory or enable remote code execution. Cites a CVE in CISA KEV.
  • Tue 27 Oct, 02:00 UTC. SecurityOnline. Palo Alto confirms critical Brotli flaw affects PAN-OS. Cites a CVE in CISA KEV.
  • Tue 27 Oct, 20:01 UTC. CISA, its first report on the story. CISA adds exploited Google Brotli flaw to KEV catalogue. Cites a CVE in CISA KEV.
  • Tue 27 Oct, 23:00 UTC. SecurityOnline. Sweet Security offers free protection against HTTP2Shell. Cites a CVE in CISA KEV.
  • Wed 28 Oct, 01:00 UTC. SecurityOnline. CISA Adds Adobe Magento and Google Brotli Flaws to KEV Catalog. Cites a CVE in CISA KEV.
  • Wed 28 Oct, 08:00 UTC. SecurityOnline. Broadcom warns of critical VMware SDDC Manager flaw. Cites a CVE in CISA KEV.
  • Wed 28 Oct, 08:01 UTC. The Hacker News. CISA Adds Two Actively Exploited Flaws to KEV Catalog. Cites a CVE in CISA KEV.
  • Wed 28 Oct, 09:30 UTC. SecurityWeek. Researchers report exploitation attempts against Brotli flaw. Cites a CVE in CISA KEV. This article, 19th of 19.
  • Known exploited CVE
  • No CVE
  • Larger: an outlet’s first report
  • Square: official source
  • Coverage over time
Show all 19 articles as a list
  1. Wed 21 OctDay 01
    1. Node.js fixes Brotli flaw that could enable remote code execution17:54 · SecurityOnline · First report · Exploited CVE · Known exploited CVE

  2. Quiet for 2 days

    Fri 23 OctDay 21
    1. Node.js Brotli flaw enables remote code execution in Linux arm64 builds08:35 · The Hacker News · Known exploited CVE
  3. Sat 24 OctDay 31
    1. Brotli Flaw Enables Code Execution in Unpatched Node.js Builds11:00 · The Hacker News · Known exploited CVE
  4. Sun 25 OctDay 41
    1. OpenAI Agents Expose VM Escapes and Sandbox Weaknesses08:30 · The Hacker News · Known exploited CVE
  5. Mon 26 OctDay 58
    1. Brotli flaw expands Node2Shell risk across HTTP applications01:30 · SecurityOnline · Known exploited CVE
    2. Microsoft issues out of band .NET fixes for four flaws03:19 · SecurityOnline · Known exploited CVE
    3. Brotli flaw triggers security updates across major software11:00 · SecurityWeek · Known exploited CVE
    Show 5 more from 26 Oct
    1. Brotli flaw exposes Python packages to remote code execution13:00 · SOCRadar · Known exploited CVE
    2. Microsoft patches critical .NET flaw that risks memory corruption13:30 · Infosecurity · Known exploited CVE
    3. Weekly recap tracks PHP and Node.js RCE flaws and supply chain attacks15:31 · The Hacker News · Known exploited CVE
    4. PHP releases rebuilt Windows packages to fix Brotli flaw18:30 · The Hacker News · Known exploited CVE
    5. Node.js Brotli flaw could expose memory or enable remote code execution19:00 · Rapid7 · Known exploited CVE
  6. Tue 27 OctDay 63
    1. Palo Alto confirms critical Brotli flaw affects PAN-OS02:00 · SecurityOnline · Known exploited CVE
    2. CISA adds exploited Google Brotli flaw to KEV catalogue20:01 · CISA · official · CISA alert · Known exploited CVE
    3. Sweet Security offers free protection against HTTP2Shell23:00 · SecurityOnline · Known exploited CVE
  7. Wed 28 OctDay 74
    1. CISA Adds Adobe Magento and Google Brotli Flaws to KEV Catalog01:00 · SecurityOnline · Known exploited CVE
    2. Broadcom warns of critical VMware SDDC Manager flaw08:00 · SecurityOnline · Known exploited CVE
    3. CISA Adds Two Actively Exploited Flaws to KEV Catalog08:01 · The Hacker News · Known exploited CVE
    4. Researchers report exploitation attempts against Brotli flaw09:30 · SecurityWeek · Known exploited CVE · This article, 19th of 19

Sources

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