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NVD / CVE Program· CNA Linux

CVE-2026-64564: sctp: don't free the ASCONF's own transport in DEL-IP processing

Noroxi assessment

Priority: Monitor (action score 39/100)

  • Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
  • Probability of exploitation in the next 30 days: 1.4% (FIRST EPSS); higher than 73% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: Linux Linux 2b324ba3494ae958cba16a453e3e71489b4de7fc, 74e8f3e7114f0e26d1b2c4c048044db9fcc27603, 85aca407c560aba81b5ce9d3d6cf94c74077d19b; azl3 kernel 6.6.145.2-1 on Azure Linux 3.0 6.6.150.1-1.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 2b324ba3494ae958cba16a453e3e71489b4de7fc, 74e8f3e7114f0e26d1b2c4c048044db9fcc27603, 85aca407c560aba81b5ce9d3d6cf94c74077d19b; azl3 kernel 6.6.145.2-1 on Azure Linux 3.0 6.6.150.1-1 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

In the Linux kernel, the following vulnerability has been resolved: sctp: don't free the ASCONF's own transport in DEL-IP processing sctp_process_asconf() caches the transport the ASCONF chunk is processed against in asconf->transport (== chunk->transport, set once in sctp_rcv()). For an ASCONF located through its Address Parameter by __sctp_rcv_asconf_lookup(), that cached transport corresponds to the Address Parameter, which need not be the packet's source address. sctp_process_asconf_param() rejects a DEL-IP for the packet source address (ADDIP D8, SCTP_ERROR_DEL_SRC_IP), but nothing protects asconf->transport. A single ASCONF can therefore carry, in order: [Address Parameter L] [DEL-IP L] [DEL-IP 0.0.0.0] where L differs from the source. The DEL-IP for L passes the D8 check and calls sctp_assoc_rm_peer() on the transport that asconf->transport still points at, freeing it (RCU-deferred). The following wildcard DEL-IP then reuses the now-dangling asconf->transport in sctp_assoc_set_primary() and sctp_assoc_del_nonprimary_peers(): set_primary() dereferences the freed transport (->ipaddr, ->state) and plants the dangling pointer into asoc->peer.primary_path / active_path, and del_nonprimary_peers(), keeping only the pointer that is no longer on the list, removes every real transport, leaving the association with a transport_count of 0 and primary_path/active_path pointing at freed memory. Reject a DEL-IP that targets the transport the ASCONF is being processed against, mirroring the existing source-address guard, so the wildcard branch can never reuse a freed transport.

CriticalCVSS 9.8 · v3.1—Proof of concept Fix available
Published
Aug 4, 2026
Updated
Oct 19, 2026
EPSS
1.4% · 73th percentile

Report tools

JSON

Action score

39

Monitor

Low priority for now.

CVSS
39 / 40 · 9.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 1.4%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · Linux
9.8
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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  • Not in KEV: no record of exploitation in the wild
  • Proof of concept exists, no weaponized module
  • A fix has been released

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Noroxi 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.

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Affected 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.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 2.6.25affected
    • 42e30bf3463cd37d73839376662cb79b4d5c416c and later · before a9ce31be4cb1a5dd82b3e0a1d0c3e7cbdcd31293affected · git
    • 42e30bf3463cd37d73839376662cb79b4d5c416c and later · before a63afa1f9b12d5293cbe0b77fd45dc0632533a13affected · git
    • 42e30bf3463cd37d73839376662cb79b4d5c416c and later · before 2b324ba3494ae958cba16a453e3e71489b4de7fcaffected · git
    • 42e30bf3463cd37d73839376662cb79b4d5c416c and later · before fedeb4468987bcaff85fe3061de5ae052d414740affected · git
    • 42e30bf3463cd37d73839376662cb79b4d5c416c and later · before 74e8f3e7114f0e26d1b2c4c048044db9fcc27603affected · git
    • 42e30bf3463cd37d73839376662cb79b4d5c416c and later · before 85aca407c560aba81b5ce9d3d6cf94c74077d19baffected · git
    • 42e30bf3463cd37d73839376662cb79b4d5c416c and later · before d136b29bf91dd8e3161281b87de597b7311d9462affected · git
    • 42e30bf3463cd37d73839376662cb79b4d5c416c and later · before 9b2854f86f0b56e9027d68e7a3fc909d1a9b566faffected · git
    • before 2.6.25not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:10kernel-64k-debug-develbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-64k-debug-devel-matchedbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-64k-develbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-64k-devel-matchedbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-debug-develbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-debug-devel-matchedbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-develbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-devel-matchedbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-docbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-headersbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-zfcpdump-develbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10kernel-zfcpdump-devel-matchedbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10perfbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:10python3-perfbefore 6.12.0-211.59.1.el10_26.12.0-211.59.1.el10_2
AlmaLinux:8bpftoolbefore 4.18.0-553.167.1.el8_104.18.0-553.167.1.el8_10
AlmaLinux:8kernelbefore 4.18.0-553.167.1.el8_104.18.0-553.167.1.el8_10
AlmaLinux:8kernel-abi-stablelistsbefore 4.18.0-553.167.1.el8_104.18.0-553.167.1.el8_10
AlmaLinux:8kernel-corebefore 4.18.0-553.167.1.el8_104.18.0-553.167.1.el8_10
AlmaLinux:8kernel-cross-headersbefore 4.18.0-553.167.1.el8_104.18.0-553.167.1.el8_10
AlmaLinux:8kernel-debugbefore 4.18.0-553.167.1.el8_104.18.0-553.167.1.el8_10
AlmaLinux:8kernel-debug-corebefore 4.18.0-553.167.1.el8_104.18.0-553.167.1.el8_10
AlmaLinux:8kernel-debug-develbefore 4.18.0-553.167.1.el8_104.18.0-553.167.1.el8_10
AlmaLinux:8kernel-debug-modulesbefore 4.18.0-553.167.1.el8_104.18.0-553.167.1.el8_10
AlmaLinux:8kernel-debug-modules-extrabefore 4.18.0-553.167.1.el8_104.18.0-553.167.1.el8_10

+96

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation
    40Plan
  • CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment
    40Plan
  • CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()
    40Plan

Published before and after this one in the same product

  • ← EarlierCVE-2026-64562Aug 4, 2026 · KVM: nVMX: Hide shadow VMCS right after VMCLEAR
    35Monitor
  • ← EarlierCVE-2026-64563Aug 4, 2026 · rhashtable: clear stale iter->p on table restart
    31Monitor
  • Later →CVE-2026-64565Aug 4, 2026 · Input: ims-pcu - fix heap-buffer-overflow in ims_pcu_process_data()
    0Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux2b324ba3494ae958cba16a453e3e71489b4de7fcVendor (CNA)
Linux Linux74e8f3e7114f0e26d1b2c4c048044db9fcc27603Vendor (CNA)
Linux Linux85aca407c560aba81b5ce9d3d6cf94c74077d19bVendor (CNA)
Linux Linux9b2854f86f0b56e9027d68e7a3fc909d1a9b566fVendor (CNA)
Linux Linuxa63afa1f9b12d5293cbe0b77fd45dc0632533a13Vendor (CNA)
Linux Linuxa9ce31be4cb1a5dd82b3e0a1d0c3e7cbdcd31293Vendor (CNA)
Linux Linuxd136b29bf91dd8e3161281b87de597b7311d9462Vendor (CNA)
Linux Linuxfedeb4468987bcaff85fe3061de5ae052d414740Vendor (CNA)
azl3 kernel 6.6.145.2-1 on Azure Linux 3.06.6.150.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
almalinux:bpftool4.18.0-553.167.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel4.18.0-553.167.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt4.18.0-553.167.1.rt7.508.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-core4.18.0-553.167.1.rt7.508.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug4.18.0-553.167.1.rt7.508.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-core4.18.0-553.167.1.rt7.508.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-devel4.18.0-553.167.1.rt7.508.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules4.18.0-553.167.1.rt7.508.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules-extra4.18.0-553.167.1.rt7.508.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-devel4.18.0-553.167.1.rt7.508.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-modules4.18.0-553.167.1.rt7.508.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-modules-extra4.18.0-553.167.1.rt7.508.el8_10 · AlmaLinux:8Package registry (OSV)
debian:linux6.1.187-1 · Debian:12Package registry (OSV)
debian:linux-6.126.12.101-1~deb12u1 · Debian:12Package registry (OSV)
red hat:kernel-64k-debug-debuginfo0:6.12.0-55.105.1.el10_0 · Red Hat:enterprise_linux_eus:10.0Package registry (OSV)
red hat:kernel-64k-debug-devel0:6.12.0-55.105.1.el10_0 · Red Hat:enterprise_linux_eus:10.0Package registry (OSV)
red hat:kernel-64k-debug-devel-matched0:6.12.0-55.105.1.el10_0 · Red Hat:enterprise_linux_eus:10.0Package registry (OSV)
red hat:kernel-64k-debuginfo0:6.12.0-55.105.1.el10_0 · Red Hat:enterprise_linux_eus:10.0Package registry (OSV)
red hat:kernel-64k-devel0:6.12.0-55.105.1.el10_0 · Red Hat:enterprise_linux_eus:10.0Package registry (OSV)
red hat:kernel-64k-devel-matched0:6.12.0-55.105.1.el10_0 · Red Hat:enterprise_linux_eus:10.0Package registry (OSV)
red hat:kernel-debug-debuginfo0:6.12.0-55.105.1.el10_0 · Red Hat:enterprise_linux_eus:10.0Package registry (OSV)

+18

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

  • Proof-of-concept repository on GitHub ×5

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Proof-of-concept repository on GitHubstars:72026-08-07
Proof-of-concept repository on GitHubstars:72026-08-07
Proof-of-concept repository on GitHubstars:12026-08-10
Proof-of-concept repository on GitHubstars:02026-08-11
Proof-of-concept repository on GitHubstars:22026-08-19

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.

  1. Published
  2. First PoC+3 d
  3. TodayNov 2, 2026+90 d
EPSS, last 120 days

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.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-681176 days aparttipc: clear sock->sk on the failed-insert path in tipc_sk_create()
    39Monitor
  • CVE-2026-681276 days apartila: reload IPv6 header after pskb_may_pull in checksum adjust
    39Monitor
  • CVE-2026-681446 days apartphonet: pep: fix use-after-free in pep_get_sb()
    39Monitor
  • CVE-2026-681566 days apartlibceph: refresh auth->authorizer_buf{,_len} after authorizer update
    39Monitor
  • CVE-2026-683816 days apartksmbd: pin conn during async oplock break notification
    39Monitor
  • CVE-2026-684266 days apartxfrm: fix stale skb->prev after async crypto steals a GSO segment
    39Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-416 · Use After Free

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd-secondary

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

The bug in code

The whole CWE-416 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

c
free(dev->buf);/* ... another thread is still running ... */process(dev->buf);

Fixed

c
lock(&dev->lock);free(dev->buf);dev->buf = NULL;unlock(&dev->lock);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. SSVC exploitation— → none
  2. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (14 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records