CVE-2026-88840
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk9th percentile - higher than 9% of all known CVEs
Summary
BusyBox TLS get_client_hello() reads past the end of the input buffer when parsing a truncated ClientHello message. This can result in an out-of-bounds read.
Risk Assessment
The vulnerability may lead to memory disclosure or a crash of services using BusyBox TLS. In network-exposed environments it could be triggered remotely.
Recommendation
Update BusyBox to a version containing the fix or restrict access to services using BusyBox TLS. Monitor TLS services for unusual behavior.
Other vulnerabilities in BusyBox
See all- CVE-2017-16544High
In the add_match function in libbb/lineedit.c in BusyBox through 1.27.2, the tab autocomplete feature does not sanitize filenames, potentially leading to executing any escape sequences in the terminal.
- CVE-2011-5325High
Directory traversal vulnerability in the BusyBox implementation of tar before version 1.22.0 v5 allows remote attackers to point to files outside the current working directory via a symlink.
- CVE-2016-2147High
Integer overflow in the DHCP client (udhcpc) in BusyBox before version 1.25.0 allows remote attackers to cause a denial of service (crash) via a malformed RFC1035-encoded domain name, leading to an out-of-bounds heap write.
- CVE-2016-6301High
The recv_and_process_client_pkt function in networking/ntpd.c in busybox allows remote attackers to cause a denial of service via a forged NTP packet, triggering a communication loop.
- CVE-2022-48174Critical
A stack overflow vulnerability exists in ash.c:6030 in busybox before version 1.35. In the Internet of Vehicles environment, it can be exploited from command execution to arbitrary code execution.
- CVE-2026-88839Medium
BusyBox passwd/group tokenize() references a stale endpoint pointer after trimming, causing an out-of-bounds write of heap pointers. This can lead to memory corruption.
- CVE-2026-88837Medium
BusyBox httpd treats yescrypt ($y$) password hashes as plaintext during Basic Authentication, inverting the authentication check. This may allow unauthorized access.
- CVE-2026-88835Medium
BusyBox dpkg read_package_field() steps past a NUL terminator on malformed .deb packages, causing an out-of-bounds heap read. This may lead to data disclosure or a crash.
- CVE-2026-88831Medium
BusyBox httpd IP deny rules with invalid CIDR prefix lengths fail open, leaving a parsed IP with a zeroed mask so the rule matches no clients. This may result in failure to block unwanted addresses.
- CVE-2026-88832High
BusyBox romfs volume ID parsing uses unbounded strlen on attacker-controlled metadata, causing a heap buffer overflow when processing crafted filesystem images.
Original NVD description (English source)
BusyBox TLS get_client_hello() reads past the end of the input buffer when parsing a truncated ClientHello message.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

