Malicious PDF — malware analysis report

Static analysis result for SHA-256 85fccd2e7b2f5774…

MALICIOUS

PDF

75.8 KB Created: 2009-12-03 19:43:29 Authoring application: PDF Library 5.9.8 (via PDF Library 9.7.10)
MD5: e05f0a8a71ad0bc416c58d15bb381dfe SHA-1: 0579281c7d84d816b30eb54c4ba2ae60481ac37a SHA-256: 85fccd2e7b2f5774534b6e5f5539942e9b59eb0353a9b4b57da12e2f1d395cbd
340 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link T1204.002 Malicious File

The PDF exploits multiple known vulnerabilities in Adobe Reader, specifically targeting Collab.getIcon, Collab.collectEmailInfo, and util.printf functions. Static analysis indicates that these exploits are used to execute embedded JavaScript, which is further deobfuscated into 'legacy_pdfkit_stage_000.js'. This script likely downloads and executes a second-stage payload, as suggested by ClamAV detections on extracted artifacts. The attack pattern is consistent with exploit kit delivery mechanisms.

Heuristics 10

  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (identified after JavaScript deobfuscation)
  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-36110 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36110
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PSSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
e591d6bd4f566e51ad84b4f36208e7308b2aafad0f3f0090473d400972531ec4
pdf-javascript-stream PDF /JS object 7 at offset 0x1A5 38278 bytes
legacy_pdfkit_stage_000.js
dda7b82d5e1bc5a91998619b1448eae441ecb76f2e81387b032b597e0c66222b
deobfuscated-js numeric array subtract-key decoded JavaScript at offset 0x1A5 10108 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).