Malicious PDF — malware analysis report

Static analysis result for SHA-256 84b9ff9bfc5fd868…

MALICIOUS

PDF

77.9 KB Created: 2020-07-29 22:53:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 61e39b0e9d1332cd17e4cf13aa5c8981 SHA-1: b1754d659deaca830c012164745b9b98e15f3e4b SHA-256: 84b9ff9bfc5fd868b5687a323405be969c819f335f5e483fd83310dffdb8c147
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, with one identified as a malicious redirector. The document body, though heavily obfuscated, suggests a lure related to 'Gamsat free practice test pdf'. The presence of a link farm and a critical heuristic firing for malicious redirector links strongly indicates an attempt to direct users to harmful sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.com/wb?keyword=gamsat%20free%20practice%20test%20pdf
    • http://files.pinmag.online/uploads/1/3/0/8/130874422/jivurusekafoxuf.pdf
    • http://files.austinpianoschool.com/uploads/1/3/2/3/132302732/747092.pdf
    • http://files.kmarcus.net/uploads/1/3/1/1/131163683/livunaludekebelozu.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/99231100330.pdf
    • https://cdn.shopify.com/s/files/1/0431/7180/7396/files/49668244488.pdf
    • https://cdn.shopify.com/s/files/1/0429/6579/4969/files/pematatebevodanolam.pdf
    • https://cdn.shopify.com/s/files/1/0431/1960/7962/files/nedozevapepomuvupumiwozi.pdf
    • https://cdn.shopify.com/s/files/1/0433/6844/8152/files/75938726937.pdf
    • https://cdn.shopify.com/s/files/1/0431/2314/6906/files/68946153737.pdf
    • https://cdn.shopify.com/s/files/1/0428/9167/3763/files/66594528750.pdf
    • https://cdn.shopify.com/s/files/1/0430/8631/5684/files/nodud.pdf
    • https://cdn.shopify.com/s/files/1/0433/8660/1626/files/xirepuwu.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6ef.bin
2341b02de89f5db930c1292aa116773fbae5cccc6e97a9f816b962d8e7adb01b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6EF 4872 bytes
font_01_sfnt_off0000f780.bin
7f70091cc6dd575991b03595d838b7879e2acf4495eceb9e51f7bff44d880609
pdf-font-stream PDF embedded font (sfnt) at offset 0xF780 16580 bytes