CVE Intelligence
High Memory corruption

CVE-2026-74758 — Apache bRPC: Heap Use-After-Free in RTMP Abort Message Handling

A heap use-after-free in the RTMP protocol component of Apache bRPC (versions < 1.18.0) allows a remote attacker to crash a bRPC RTMP server by sending a crafted Abort control message. No authentication or application-level request is required. Root Cause: When an RTMP Abort control message names the chunk stream that is currently being parsed (the chunk stream carrying the message itself), RtmpChunkStream::OnAbortMessage calls RtmpContext::ClearChunkStream, which deletes the RtmpChunkStream while its Feed() is still running. After the message handler returns, Feed() continues to access members of the deleted object, resulting in a heap-use-after-free. Affected Scenarios: bRPC servers that enable RTMP support (ServerOptions.rtmp_service set) and accept connections from untrusted networks. How to Fix: 1. Upgrade bRPC to version 1.18.0, which fixes this issue. 2. Apply this patch:  https://github.com/apache/brpc/pull/3452 The fix skips clearing the chunk stream when the Abort message targets the chunk stream that is currently being parsed.

Published Oct 21, 2026 · Updated Oct 30, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: apache

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.2% (30-day exploitation probability)+2
  • Technical severity (high)+6
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.24%
ahead of 16% of scored CVEs · Oct 30, 2026
Affects
Apache Software Foundation
Brpc
CVSS base
7.5
High · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Apache Software Foundation Brpc).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  4. Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Apache Software Foundation Brpc < 1.18.0 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
7.5 CVSS 3.1 High 3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database
7.5 CVSS 3.1 High — — CISA-ADP via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: 134c704f-9b21-4f2e-91b3-4a467353bcc0)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-416 · Use After Free

Other CVEs with this weakness →

EPSS over time FIRST

Oct 22, 2026 → Oct 30, 2026 · 9 reading(s) · max 0.24%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
web/proxy/WAF logsnetwork IDS/IPSendpoint telemetry (EDR)crash dumps

Timeline

What happened to this CVE, newest first.

  • 2026
  • SSVC assessment updated
    Oct 30, 2026 · CVE Program (cve.org) e CISA ADP
  • CVSS changed · 7.5
    Oct 30, 2026 · NIST National Vulnerability Database
  • Source status changed · Received → Deferred
    Oct 22, 2026 · NIST National Vulnerability Database
  • Record published
    Oct 21, 2026
  • Affected products added · apache software foundation/apache brpc
    Oct 21, 2026 · CVE Program (cve.org) e CISA ADP
  • Source status changed · → Received
    Oct 21, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 21, 2026 · Alertas do Telegram
  • CVE published
    Oct 21, 2026 · apache

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 21, 2026 – Oct 26, 2026
  • 1× Official description updated · Oct 21, 2026 – Oct 21, 2026

References

3 on the record

Elsewhere on this site

Apache Software Foundation
every CVE for this vendor
Memory corruption
same class
CWE-416
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-90484 Apache bRPC: Null pointer dereference in MySQL reply parser leading to client crash 9d
  • CVE-2026-87849 Apache bRPC: Out-of-bounds read via non-object fields in Discovery naming-service reply parsing 9d
  • CVE-2026-86249 Apache bRPC: Authentication bypass when a server sets ServerOptions.internal_port and ServerOptions.auth 9d
  • CVE-2026-86147 Apache bRPC: Arbitrary file creation/truncation via /flags and unbounded profiling duration via /pprof 9d
  • CVE-2026-86146 Apache bRPC: HTTP Request Smuggling and Header Injection via Lenient HTTP/1.1 Header Parsing 9d
  • CVE-2026-82425 Apache bRPC: Reachable Assertion in Socket::OnInputEvent Allows Remote Denial of Service 9d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-74758 is "Apache bRPC: Heap Use-After-Free in RTMP Abort Message Handling", rated High. It affects Brpc (Apache Software Foundation); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 0.24% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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