CVE-2026-89864

Description

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Bound i2c->length in I2C bsg handlers struct qla_i2c_access carries a 16-bit length field alongside a fixed 64-byte buffer: struct qla_i2c_access { uint16_t device, offset, option, length; uint8_t buffer[0x40]; } __packed; qla2x00_write_i2c() and qla2x00_read_i2c() use the user-supplied i2c->length without any bounds check. i2c is overlaid on a 256-byte on-stack buffer and sfp is a 256-byte DMA-pool buffer, so a length up to 65535 overruns both: - write: memcpy(sfp, i2c->buffer, i2c->length) over-reads the stack and over-writes the sfp heap buffer, and qla2x00_write_sfp() then DMAs i2c->length bytes out of the 256-byte buffer. - read: qla2x00_read_sfp() DMAs i2c->length bytes into the 256-byte sfp, then memcpy(i2c->buffer, sfp, i2c->length) overflows the 64-byte buffer inside the on-stack array. A caller holding CAP_SYS_RAWIO can use this to corrupt the heap and the kernel stack. Reject requests whose length exceeds the buffer before any copy or DMA transfer in both handlers.

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EPSS — Exploit Prediction

0.0021

Probability of exploitation

0.11%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/0918ee2c0eeb4d7f45b82b3dc11e65c2d9b7ad59 https://git.kernel.org/stable/c/2be39946abcde5a6416fb074ef728429e246a996 https://git.kernel.org/stable/c/32d6df14fdab71fe1ba304fd9a0db0411ea2e043 https://git.kernel.org/stable/c/47049fdadc0eaa115e813735b827e1379c0d2cf8 https://git.kernel.org/stable/c/522d6dcdc645d8f97d6b4cdfd6d8eea307f3ff0e https://git.kernel.org/stable/c/8f01f886cc5e7bbc16cbf1a9928fdebbc911e973 https://git.kernel.org/stable/c/97ca58b0fb026799b99e3d552d5f69cf9a3113ad https://git.kernel.org/stable/c/9a756f277eb89f769dbf380f38245c270d31fdb5

Frequently Asked Questions

What is CVE-2026-89864? +

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Bound i2c->length in I2C bsg handlers struct qla_i2c_access carries a 16-bit length field alongside a fixed 64-byte buffer: struct qla_i2c_access { uint16_t device, offset, option, length; uint8_t buffer[0x40]; } __packed; qla2x00_write_i2c() and qla2x00_read_i2c() use the user-supplied i2c->length without any bounds check. i2c is overlaid on a 256-byte on-stack buffer and sfp is a 256-byte DMA-pool buffer, so a length up to 65535 overruns both: - write: memcpy(sfp, i2c->buffer, i2c->length) over-reads the stack and over-writes the sfp heap buffer, and qla2x00_write_sfp() then DMAs i2c->length bytes out of the 256-byte buffer. - read: qla2x00_read_sfp() DMAs i2c->length bytes into the 256-byte sfp, then memcpy(i2c->buffer, sfp, i2c->length) overflows the 64-byte buffer inside the on-stack array. A caller holding CAP_SYS_RAWIO can use this to corrupt the heap and the kernel stack. Reject requests whose length exceeds the buffer before any copy or DMA transfer in both handlers.

How do I check if I'm vulnerable to CVE-2026-89864? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.