LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. From 1.6.26 to 1.6.53, there is an integer truncation in the libpng simplified write API functions png_write_image_16bit and png_write_image_8bit causes heap buffer over-read when the caller provides a negative row stride (for bottom-up image layouts) or a stride exceeding 65535 bytes. The bug was introduced in libpng 1.6.26 (October 2016) by casts added to silence compiler warnings on 16-bit systems. This vulnerability is fixed in 1.6.54.
Weakness
The product reads data past the end, or before the beginning, of the intended buffer.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Libpng | Libpng | 1.6.26 (including) | 1.6.54 (excluding) |
| Red Hat Enterprise Linux 10 | RedHat | libpng-2:1.6.40-8.el10_1.2 | * |
| Red Hat Enterprise Linux 10.0 Extended Update Support | RedHat | libpng-2:1.6.40-8.el10_0.2 | * |
| Red Hat Enterprise Linux 8 | RedHat | mingw-libpng-0:1.6.34-2.el8_10 | * |
| Red Hat Enterprise Linux 9 | RedHat | libpng-2:1.6.37-12.el9_7.2 | * |
| Red Hat Enterprise Linux 9 | RedHat | libpng-2:1.6.37-12.el9_7.2 | * |
| Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions | RedHat | libpng-2:1.6.37-12.el9_0.2 | * |
| Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | RedHat | libpng-2:1.6.37-12.el9_2.2 | * |
| Red Hat Enterprise Linux 9.4 Extended Update Support | RedHat | libpng-2:1.6.37-12.el9_4.2 | * |
| Red Hat Enterprise Linux 9.6 Extended Update Support | RedHat | libpng-2:1.6.37-12.el9_6.2 | * |
| Red Hat Discovery 2 | RedHat | discovery/discovery-ui-rhel9:sha256:f80b4635aa39ed1f1633277939dd8a54374a65fc9fd24cc31a4bd88cdc3cde6d | * |
| Chromium-browser | Ubuntu | upstream | * |
| Libpng1.6 | Ubuntu | devel | * |
| Libpng1.6 | Ubuntu | esm-infra/bionic | * |
| Libpng1.6 | Ubuntu | esm-infra/focal | * |
| Libpng1.6 | Ubuntu | jammy | * |
| Libpng1.6 | Ubuntu | noble | * |
| Libpng1.6 | Ubuntu | plucky | * |
| Libpng1.6 | Ubuntu | questing | * |
| Libpng1.6 | Ubuntu | upstream | * |
| Thunderbird | Ubuntu | plucky | * |
Potential Mitigations
- Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.