CVE-2026-87849: Apache bRPC: Out-of-bounds read via non-object fields in Discovery naming-service reply parsing
Noroxi assessment
Priority: Monitor (action score 17/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.35% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: Apache Software Foundation Apache bRPC 1.18.0.
Low priority for now. Upgrade to Apache Software Foundation Apache bRPC 1.18.0 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
The Discovery naming-service reply parser in Apache bRPC (versions < 1.18.0) calls RapidJSON object-only accessors (FindMember) on JSON values without first validating that those values are objects. A malformed Discovery response whose data/service members or instances list contain non-object entries (e.g. a bare integer) triggers the RapidJSON object-access precondition on the client, reading memory out of bounds and potentially crashing the bRPC client. Root Cause: In src/brpc/policy/discovery_naming_service.cpp, DiscoveryNamingService::GetServers() and DiscoveryNames::ListDiscoveryNodes() access JSON values with member functions on non-object values. RapidJSON only defines these operations for object types; invoking them on a non-object violates the class invariant and results in undefined behavior (out-of-bounds read), commonly crashing the process. Affected Scenarios: An operator-configured (or compromised) Discovery backend returns a malformed /discovery/nodes or /discovery/fetchs response whose data/service/instance entries are not JSON objects, crashing any bRPC client that refreshes its server list. How to Fix: 1. Upgrade bRPC to version 1.18.0 or later, which fixes this issue. 2. Apply this patch: https://github.com/apache/brpc/pull/3533 The fix validates that the Discovery response data, per-service data, and instance entries are JSON objects (and skips non-object node/instance entries and rejects non-object data/service values) before calling member accessors.
- Published
- Oct 21, 2026
- Updated
- Oct 26, 2026
- EPSS
- 0.3% · 29th percentile
- CWE
- CWE-125
Report tools
Action score
17
Low priority for now.
- CVSS
- 17 / 40 · 4.3 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
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Versions reported by the vendor
Affected version ranges reported by the assigning authority (apache). Independent of NVD's CPE analysis and usually ahead of it.
Apache Software Foundation Apache bRPC
- before 1.18.0affected · semver
Same product
apache software foundation: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-86249Apache bRPC: Authentication bypass when a server sets ServerOptions.internal_port and ServerOptions.auth36Monitor
- CVE-2026-78334Apache bRPC: Missing Authentication for Streaming RPC Frames36Monitor
- CVE-2026-56388Apache bRPC: Out-of-Bounds Write in Redis Command Parser36Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-86146Oct 21, 2026 · Apache bRPC: HTTP Request Smuggling and Header Injection via Lenient HTTP/1.1 Header Parsing30Monitor
- ← EarlierCVE-2026-86147Oct 21, 2026 · Apache bRPC: Arbitrary file creation/truncation via /flags and unbounded profiling duration via /pprof30Monitor
- Later →CVE-2026-90484Oct 21, 2026 · Apache bRPC: Null pointer dereference in MySQL reply parser leading to client crash26Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Apache Software Foundation Apache bRPC | 1.18.0 | Vendor (CNA) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- TodayNov 12, 2026+22 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- Claudefinder
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-563860 days apartApache bRPC: Integer Underflow and Out-of-Bounds Read in HTTP/2 DATA Frame Parser30Monitor
- CVE-2026-619160 days apartApache bRPC: Out-of-bounds Read in URL and Header Lookup Tables on Unsigned-char Platforms30Monitor
- CVE-2026-797040 days apartApache bRPC: Out-of-bounds Read in Multi-stream RPC Response Handling30Monitor
Not on record for this CVE: public bounty program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- low · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- Low
Weakness class (CWE)
CWE-125 · Out-of-bounds ReadCVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- SSVC exploitation— → none
- CVSS— → 4.3
- Severity— → medium
- Exploit maturity— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.