| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
i2c: rtl9300: ensure data length is within supported range
Add an explicit check for the xfer length to 'rtl9300_i2c_config_xfer'
to ensure the data length isn't within the supported range. In
particular a data length of 0 is not supported by the hardware and
causes unintended or destructive behaviour.
This limitation becomes obvious when looking at the register
documentation [1]. 4 bits are reserved for DATA_WIDTH and the value
of these 4 bits is used as N + 1, allowing a data length range of
1 <= len <= 16.
Affected by this is the SMBus Quick Operation which works with a data
length of 0. Passing 0 as the length causes an underflow of the value
due to:
(len - 1) & 0xf
and effectively specifying a transfer length of 16 via the registers.
This causes a 16-byte write operation instead of a Quick Write. For
example, on SFP modules without write-protected EEPROM this soft-bricks
them by overwriting some initial bytes.
For completeness, also add a quirk for the zero length.
[1] https://svanheule.net/realtek/longan/register/i2c_mst1_ctrl2 |
| In the Linux kernel, the following vulnerability has been resolved:
tcp: Correct signedness in skb remaining space calculation
Syzkaller reported a bug [1] where sk->sk_forward_alloc can overflow.
When we send data, if an skb exists at the tail of the write queue, the
kernel will attempt to append the new data to that skb. However, the code
that checks for available space in the skb is flawed:
'''
copy = size_goal - skb->len
'''
The types of the variables involved are:
'''
copy: ssize_t (s64 on 64-bit systems)
size_goal: int
skb->len: unsigned int
'''
Due to C's type promotion rules, the signed size_goal is converted to an
unsigned int to match skb->len before the subtraction. The result is an
unsigned int.
When this unsigned int result is then assigned to the s64 copy variable,
it is zero-extended, preserving its non-negative value. Consequently, copy
is always >= 0.
Assume we are sending 2GB of data and size_goal has been adjusted to a
value smaller than skb->len. The subtraction will result in copy holding a
very large positive integer. In the subsequent logic, this large value is
used to update sk->sk_forward_alloc, which can easily cause it to overflow.
The syzkaller reproducer uses TCP_REPAIR to reliably create this
condition. However, this can also occur in real-world scenarios. The
tcp_bound_to_half_wnd() function can also reduce size_goal to a small
value. This would cause the subsequent tcp_wmem_schedule() to set
sk->sk_forward_alloc to a value close to INT_MAX. Further memory
allocation requests would then cause sk_forward_alloc to wrap around and
become negative.
[1]: https://syzkaller.appspot.com/bug?extid=de6565462ab540f50e47 |
| [This CNA information record relates to multiple CVEs; the
text explains which aspects/vulnerabilities correspond to which CVE.]
The directory and Rock Ridge / SUSP walk in libfsimage's iso9660 driver
derives several lengths directly from attacker-controlled on-disk fields
without validating them:
* The directory loop itself assumes a good record length. This is
CVE-2026-42494.
* The calculation of the System Use area may underflow. This is
CVE-2026-42495.
* The Rock Ridge extension loop assumes a good (inner) record length.
This is CVE-2026-62423.
* The Rock Ridge NM record processing assumes a good entry length.
This is CVE-2026-62424.
* The Rock Ridge CE record processing assumes a good size and offset.
This is CVE-2026-62425. |
| gopacket provides packet processing capabilities for Go. In version 1.6.0 and earlier, the Diameter AVP decoder computes an AVP data length by subtracting a fixed header size from an attacker-controlled AVP Length field, so a vendor-flagged AVP whose Length is smaller than the 12-byte header underflows the unsigned 32-bit value and drives an unbounded allocation of roughly 4 GiB, and two such messages in succession OOM-kill a collector, causing an unauthenticated remote denial of service. This issue is fixed in version 1.6.1. |
| In the Linux kernel, the following vulnerability has been resolved:
misc: fastrpc: fix DMA address corruption due to find_vma misuse
fastrpc_get_args() uses find_vma() to look up the VMA for a user-provided
pointer and compute a DMA address offset. When the address falls in a gap
before the returned VMA, (ptr & PAGE_MASK) - vma->vm_start underflows,
corrupting the DMA address sent to the DSP.
Replace find_vma() with vma_lookup(), which returns NULL when the address
is not contained within any VMA. |
| libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2_cipher_crypt() function in src/openssl.c that allows a malicious SSH server to crash any connecting client by negotiating AES-GCM ciphers during handshake. Attackers can exploit the underflow in the expression computing blocksize minus aadlen minus authentication tag length to trigger an out-of-bounds read and a memcpy call with a near-SIZE_MAX length argument, causing immediate process crash before any authentication occurs. |
| FFmpeg through 8.1.2 contains an out-of-bounds write vulnerability that allows attackers to cause heap corruption by supplying a crafted ffconcat file processed with the -safe 0 flag. The TY demuxer's demux_audio() function decrements packet size without bounds checking, producing a negative size value that is passed to memcpy() in shorten_decode_frame(), where conversion to size_t wraps the value to near SIZE_MAX and triggers reads beyond the source allocation and writes far beyond the Shorten decoder's bitstream buffer. |
| libheif is a HEIF and AVIF file format decoder and encoder. Versions 1.19.0 through 1.21.2 have a heap OOB read in ImageItem_Grid::decode_grid_tile via irot-induced tile-coordinate underflow. Version 1.22.0 fixes the issue. |
| Out-of-bounds Write, Integer Underflow (Wrap or Wraparound) vulnerability in Apache NimBLE BASS service.
Improper validation when parsing BASS service "Add Source" and "Modify Source" operation PDU could results in stack buffer overflow or arbitrary out-of-bound read.
This can be triggered by nearby devices over Bluetooth connection, however pairing is required prior to accessing BASS service, which depending on device configuration may or may not require user action.
This issue affects Apache NimBLE: through 1.9.0.
Users are recommended to upgrade to version 1.10.0, which fixes the issue. |
| Wazuh is a free and open source platform used for threat prevention, detection, and response. In versions 3.0.0 and above, prior to 4.14.5, a size_t integer underflow in os_crypto/shared/msgs.c:389 allows any enrolled Wazuh agent to crash the wazuh-remoted process on the manager, immediately disconnecting all agents from the manager. A second code path reached by the same underflow may allow heap memory corruption. This issue has been fixed in version 4.14.5. |
| Integer underflow (wrap or wraparound) in Microsoft Office Excel allows an unauthorized attacker to execute code locally. |
| U-Boot through 2026.04-rc3 contains an integer underflow vulnerability in the tcp_rx_state_machine() function (net/tcp.c) that allows a network-adjacent attacker to crash the bootloader by sending a malformed TCP SYN+ACK packet with a manipulated data offset field causing payload_len to become negative. When the TCP_SYN_SENT handler calls tcp_rx_user_data() without invoking tcp_seg_in_wnd() validation, the negative payload_len is implicitly converted to a large unsigned integer (e.g., 0xFFFFFFD8) and passed to memcpy() in store_block(), causing an immediate crash that prevents device boot and may enable memory corruption when CONFIG_LMB is disabled. |
| Integer underflow (wrap or wraparound) in Microsoft Defender allows an unauthorized attacker to execute code locally. |
| strongSwan versions 4.5.0 prior to 6.0.5 contain an integer underflow vulnerability in the EAP-TTLS AVP parser that allows unauthenticated remote attackers to cause a denial of service by sending crafted AVP data with invalid length fields during IKEv2 authentication. Attackers can exploit the failure to validate AVP length fields before subtraction to trigger excessive memory allocation or NULL pointer dereference, crashing the charon IKE daemon. |
| Integer underflow (wrap or wraparound) in Microsoft Office allows an unauthorized attacker to execute code locally. |
| OpenWrt is a Linux operating system targeting embedded devices. Before v25.12.5, an integer underflow in handle_send_a() of the Emergency Access Daemon allows any unauthenticated attacker on the local network to crash the daemon by sending a single crafted UDP packet. The message length underflows before a bounds check and is then passed to memcpy as a very large size. This issue is fixed v25.12.5. |
| Nmap through 7.99 does not keep the IPv6 extension-header walk within the captured packet in ipv6_get_data_primitive (libnetutil/netutil.cc), so the pointer advances past the buffer and the remaining-length computation underflows to a large value. A scanned target or on-path attacker returning a crafted IPv6 response with a truncated extension header can trigger out-of-bounds reads and a crash during raw IPv6 scans. |
| In the Linux kernel, the following vulnerability has been resolved:
batman-adv: fix tp_meter counter underflow during shutdown
batadv_tp_sender_shutdown() unconditionally decrements the "sending"
atomic counter. If multiple paths (e.g. timeout, user cancel, and
normal finish) call this function, the counter can underflow to -1.
Since the sender logic treats any non-zero value as "still sending",
a negative value causes the sender kthread to loop indefinitely.
This leads to a use-after-free when the interface is removed while
the zombie thread is still active.
Fix this by using atomic_xchg() to ensure the counter only transitions
from 1 to 0 once.
[sven: added missing change in batadv_tp_send] |
| libnfs through 6.0.2 before 935b8db has an xid integer underflow in READ_IOVEC in rpc_read_from_socket in lib/socket.c during a connection to a crafted NFS server, when the expected pdu size exceeds the absolute pdu size from the xid/record-marker. |
| Integer underflow in wc_PKCS7_DecryptOri when handling crafted Other Recipient Info, leading to incorrect length handling during decryption. |
