[PPSC-602] CWE-253: Unchecked cursor control writes#126
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…s (CWE-253) Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Test Coverage Reporttotal: (statements) 80.8% Coverage by function |
|
| Severity | Count |
|---|---|
| 🟡 MEDIUM | 1 |
| 🔵 LOW | 5 |
Total: 6
View all 6 findings
🟡 MEDIUM (1)
CWE-253_armis-cli_38295677_internal/progress/progress.go_222_3_222_3 - The deferred call `fmt.Fprint(s.writer, cursorShow)` (line 222) discards its return value by assigning it to the blank identifier
Location: internal/progress/progress.go:222
The deferred call fmt.Fprint(s.writer, cursorShow) (line 222) discards its return value by assigning it to the blank identifier. This means any write error from the spinner's output writer is ignored, which matches CWE‑253: Incorrect Check of Function Return Value. Although the comment notes this is intentional for terminal control sequences, the practice still masks potential failures if the writer is redirected to a non‑terminal destination (e.g., a pipe or network stream). The spinner is used in a CLI context with a hard‑coded default writer (os.Stderr), so the exposure is limited to internal code (exposure level 1). No external user input reaches the fmt.Fprint call, so taint does not propagate to this sink. The issue is a true positive for the specified CWE.
CWEs: CWE-253: Incorrect Check of Function Return Value
🔵 LOW (5)
CWE-253_armis-cli_38295677_internal/progress/progress.go_259_6_259_69 - At line 259 the code calls fmt.Fprintf to write spinner output but discards both the number of bytes written and the error value (`_, _ = fmt.Fprintf(...)`)
Location: internal/progress/progress.go:259
At line 259 the code calls fmt.Fprintf to write spinner output but discards both the number of bytes written and the error value (_, _ = fmt.Fprintf(...)). This matches CWE‑253: Incorrect Check of Function Return Value, because any write failure is silently ignored, potentially hiding I/O errors. The spinner runs in a CLI context with the writer defaulting to os.Stderr (a static, internal output stream), so the vulnerability is not exposed to external network interfaces. An attacker who could supply a custom writer might cause write errors that go unnoticed, leading to loss of progress feedback, but the impact is limited to denial‑of‑service‑like behavior within the local CLI tool. No user‑controlled data flows into the fmt.Fprintf call, so taint analysis is not applicable. The overall risk is low with a static exposure level.
CWEs: CWE-253: Incorrect Check of Function Return Value
CWE-253_armis-cli_38295677_internal/progress/progress.go_257_6_257_79 - In the spinner's rendering loop, the code calls `fmt.Fprintf` to write the spinner frame, message, and timer to the configured writer
Location: internal/progress/progress.go:257
In the spinner's rendering loop, the code calls fmt.Fprintf to write the spinner frame, message, and timer to the configured writer. The function's return values (bytes written and error) are deliberately discarded with blank identifiers. This constitutes an incorrect check of the function's return value, matching CWE‑253. Because the writer defaults to os.Stderr (a static, internal output stream) and can only be changed programmatically, no external user input reaches this call, so the issue does not expose sensitive data or provide an attack surface beyond the CLI process itself. The main risk is that write errors (e.g., when the output stream is closed or unavailable) are silently ignored, potentially leaving the spinner in an inconsistent state, but the impact is limited to the local execution environment.
CWEs: CWE-253: Incorrect Check of Function Return Value
CWE-253_armis-cli_38295677_internal/progress/progress.go_245_5_245_44 - At line 245 the code calls `fmt.Fprint` to write a clear‑line escape sequence, but both the number of bytes written and the error value are discarded (`_, _ =`)
Location: internal/progress/progress.go:245
At line 245 the code calls fmt.Fprint to write a clear‑line escape sequence, but both the number of bytes written and the error value are discarded (_, _ =). This matches CWE‑253, which concerns failing to check a function’s return value. The omission is intentional for terminal control, yet it still represents an incorrect check of the return value, so the finding is a true positive for the reported CWE. The spinner operates only within a command‑line tool, writing to stderr; it is not exposed via network interfaces, placing its exposure at level 5 (internal script‑to‑script interaction). Consequently, the likelihood of exploitation is low (value 5). No user‑controlled data reaches this call, so taint analysis is not applicable.
CWEs: CWE-253: Incorrect Check of Function Return Value
CWE-253_armis-cli_38295677_internal/progress/progress.go_241_5_241_44 - The code at line 241 calls `fmt.Fprint` to clear the terminal line but deliberately discards both the number of bytes written and any error returned (`_, _ = fmt.Fprint(...)`)
Location: internal/progress/progress.go:241
The code at line 241 calls fmt.Fprint to clear the terminal line but deliberately discards both the number of bytes written and any error returned (_, _ = fmt.Fprint(...)). This constitutes an incorrect check of the function's return value, which matches CWE‑253. The comment in the source acknowledges the omission as intentional, but the pattern still represents the specific flaw described by the CWE. No external input influences this call, and the spinner operates only within a command‑line interface, so the vulnerability is not exposed to network attackers. Consequently, the exposure level is low (static/internal usage), leading to a low likelihood of exploitation and a LOW overall severity rating.
CWEs: CWE-253: Incorrect Check of Function Return Value
CWE-253_armis-cli_38295677_internal/progress/progress.go_221_4_221_61 - The code at line 221 (and line 220) calls `fmt.Fprint` to write terminal control sequences but discards both the number of bytes written and any error returned (`_, _ = fmt.Fprint(...)`)
Location: internal/progress/progress.go:221
The code at line 221 (and line 220) calls fmt.Fprint to write terminal control sequences but discards both the number of bytes written and any error returned (_, _ = fmt.Fprint(...)). This matches CWE‑253, which concerns ignoring the return value of a function that can fail. Because the return value is never checked, write errors (e.g., when the writer is closed, not a terminal, or otherwise fails) go unnoticed, potentially leaving the spinner in an inconsistent state. The spinner is part of a command‑line interface that users invoke directly, making the functionality publicly reachable. Consequently, the vulnerability is exposed to any user running the CLI tool. No user‑controlled data flows into the fmt.Fprint calls, so there is no taint propagation to consider. The issue is a true positive for CWE‑253.
CWEs: CWE-253: Incorrect Check of Function Return Value
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Summary
Test plan
go build ./...)Generated with Claude Code