CVE-2026-65609
Out-of-bounds write in nnn
nnn is vulnerable to Out-of-Bound write vulnerability. Due to lack of validation of attacker-controlled length fields deserialized from a session file, a crafted session file can cause nnn to write data beyond the bounds of fixed-size global buffers when loaded with the -s option. An attacker who can place a malicious session file in the victim's nnn session directory can exploit this to corrupt adjacent global state.
Maintainer of this project was notified about this vulnerability. It might has been addressed, but the maintainer did not provide a vulnerable version range. Only version 5.2 was tested and confirmed as vulnerable.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Active
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
2.4
Out-of-bounds write in nnn
nnn is vulnerable to Out-of-Bound write vulnerability. Due to lack of validation of attacker-controlled length fields deserialized from a session file, a crafted session file can cause nnn to write data beyond the bounds of fixed-size global buffers when loaded with the -s option. An attacker who can place a malicious session file in the victim's nnn session directory can exploit this to corrupt adjacent global state.
Maintainer of this project was notified about this vulnerability. It might has been addressed, but the maintainer did not provide a vulnerable version range. Only version 5.2 was tested and confirmed as vulnerable.
- Record
CVE-2026-65609- CVSS 4.0
- 2.4 Low
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-787
- Updated
- 2026-11-02
EUVDEUVD-2026-62398
2.4
nnn is vulnerable to Out-of-Bound write vulnerability. Due to lack of validation of attacker-controlled length fields deserialized from a session file, a crafted session file can cause nnn to write data beyond the bounds of fixed-size global buffers when loaded with the -s option. An attacker who can place a malicious session file in the victim's nnn session directory can exploit this to corrupt adjacent global state.
Maintainer of this project was notified about this vulnerability. It might has been addressed, but the maintainer did not provide a vulnerable version range. Only version 5.2 was tested and confirmed as vulnerable.
- Record
EUVD-2026-62398- CVSS 4.0
- 2.4 Low
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-r4wp-c597-23pf
2.4
nnn is vulnerable to Out-of-Bound write vulnerability. Due to lack of validation of attacker...
nnn is vulnerable to Out-of-Bound write vulnerability. Due to lack of validation of attacker-controlled length fields deserialized from a session file, a crafted session file can cause nnn to write data beyond the bounds of fixed-size global buffers when loaded with the -s option. An attacker who can place a malicious session file in the victim's nnn session directory can exploit this to corrupt adjacent global state.
Maintainer of this project was notified about this vulnerability. It might has been addressed, but the maintainer did not provide a vulnerable version range. Only version 5.2 was tested and confirmed as vulnerable.
- Record
GHSA-r4wp-c597-23pf- CVSS 4.0
- 2.4 Low
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-787
- Updated
- 2026-11-02
NVD
2.4
nnn is vulnerable to Out-of-Bound write vulnerability. Due to lack of validation of attacker-controlled length fields deserialized from a session file, a crafted session file can cause nnn to write data beyond the bounds of fixed-size global buffers when loaded with the -s option. An attacker who can place a malicious session file in the victim's nnn session directory can exploit this to corrupt adjacent global state.
Maintainer of this project was notified about this vulnerability. It might has been addressed, but the maintainer did not provide a vulnerable version range. Only version 5.2 was tested and confirmed as vulnerable.
- Record
CVE-2026-65609- CVSS 4.0
- 2.4 Low
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-787
- Updated
- 2026-11-02
OSV
2.4
Out-of-bounds write in nnn
nnn is vulnerable to Out-of-Bound write vulnerability. Due to lack of validation of attacker-controlled length fields deserialized from a session file, a crafted session file can cause nnn to write data beyond the bounds of fixed-size global buffers when loaded with the -s option. An attacker who can place a malicious session file in the victim's nnn session directory can exploit this to corrupt adjacent global state.
Maintainer of this project was notified about this vulnerability. It might has been addressed, but the maintainer did not provide a vulnerable version range. Only version 5.2 was tested and confirmed as vulnerable.
- Record
CVE-2026-65609- CVSS 4.0
- 2.4 Low
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-787
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-65609
2.4
nnn is vulnerable to Out-of-Bound write vulnerability. Due to lack of validation of attacker-controlled length fields deserialized from a session file, a crafted session file can cause nnn to write data beyond the bounds of fixed-size global buffers when loaded with the -s option. An attacker who can place a malicious session file in the victim's nnn session directory can exploit this to corrupt adjacent global state. Maintainer of this project was notified about this vulnerability. It might has been addressed, but the maintainer did not provide a vulnerable version range. Only version 5.2 was tested and confirmed as vulnerable.
- Record
DEBIAN-CVE-2026-65609- CVSS 4.0
- 2.4 Low
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-65609
2.4
nnn is vulnerable to Out-of-Bound write vulnerability. Due to lack of validation of attacker-controlled length fields deserialized from a session file, a crafted session file can cause nnn to write data beyond the bounds of fixed-size global buffers when loaded with the -s option. An attacker who can place a malicious session file in the victim's nnn session directory can exploit this to corrupt adjacent global state. Maintainer of this project was notified about this vulnerability. It might has been addressed, but the maintainer did not provide a vulnerable version range. Only version 5.2 was tested and confirmed as vulnerable.
- Record
UBUNTU-CVE-2026-65609- CVSS 4.0
- 2.4 Low
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
nnnDebian:12 |
All versions, plus listed versions 4.7-14.8-14.9-15.0-15.1-15.2-15.3-1 |
None known |
nnnDebian:13 |
All versions, plus listed versions 5.0-15.1-15.2-15.3-1 |
None known |
nnnDebian:14 |
All versions, plus listed versions 5.0-15.1-15.2-15.3-1 |
None known |
nnnUbuntu:18.04:LTS |
All versions, plus listed versions 1.3-21.5-11.6-11.7-1 |
None known |
nnnUbuntu:20.04:LTS |
All versions, plus listed versions 2.6-12.7-12.8-12.8.1-12.9-13.0-13.0-2 |
None known |
nnnUbuntu:22.04:LTS |
All versions, plus listed versions 3.5-14.3-1 |
None known |
nnnUbuntu:24.04:LTS |
All versions, plus listed versions 4.8-14.9-14.9-1build14.9-1build2 |
None known |
nnnUbuntu:26.10 |
All versions, plus listed versions 5.1-15.2-15.3-1 |
None known |
nnnUbuntu:26.04:LTS |
All versions, plus listed versions 5.0-15.1-1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-65609 is a low vulnerability (CVSS 2.4) in Jarun Nnn, published August 19, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.15%, the 4th percentile. No source names a fixed version.
References
cert.pl/en/posts/2026/08/CVE-2026-65609
nvd.nist.gov/vuln/detail/CVE-2026-65609
github.com/advisories/GHSA-r4wp-c597-23pf
github.com/CVEProject/cvelistV5/tree/main/cves/2026/65xxx/CVE-2026-65609.json
github.com/jarun/nnn
security-tracker.debian.org/tracker/CVE-2026-65609
ubuntu.com/security/CVE-2026-65609
cve.org/CVERecord?id=CVE-2026-65609