Malicious PDF — malware analysis report

Static analysis result for SHA-256 2912ebc4e2de5346…

MALICIOUS

PDF

42.3 KB Created: 2020-08-10 08:57:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fa98213d063a78ae4c4e05766a684009 SHA-1: a32daf01c3023a1e4aa7461dd39bd590d2293d9f SHA-256: 2912ebc4e2de53464efca27b232216a951b2eead3bf276c89c5e3343e7da3aca
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs, with a critical heuristic firing for a malicious redirector link. The document body, though heavily obfuscated, contains text related to 'ejercicios de brain gym pdf' and the malicious redirector URL. The presence of a large number of external PDF links suggests an SEO manipulation or link farm tactic, potentially to distribute further malicious content or improve search engine ranking for malicious sites. No scripts were extracted, limiting the analysis of direct payload execution.

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.cc/pify?keyword=ejercicios+de+brain+gym+pdf
    • http://files.mrsreid3rdgrade.com/uploads/1/3/1/4/131483019/8410060.pdf
    • http://pumaxe.cocktailsnponytails.com/uploads/1/3/0/7/130739379/5965047.pdf
    • http://files.teamfsi.net/uploads/1/3/2/6/132695416/7565e590.pdf
    • https://cdn.shopify.com/s/files/1/0430/8385/8074/files/63963275002.pdf
    • https://cdn.shopify.com/s/files/1/0430/1537/2953/files/52268067090.pdf
    • https://cdn.shopify.com/s/files/1/0429/4203/8182/files/satufirupa.pdf
    • https://cdn.shopify.com/s/files/1/0437/1555/9573/files/tokopuwexog.pdf
    • https://cdn.shopify.com/s/files/1/0433/8833/8330/files/buzabanex.pdf
    • https://cdn.shopify.com/s/files/1/0429/8748/7395/files/becoming_a_better_you.pdf
    • https://cdn.shopify.com/s/files/1/0432/2567/7982/files/apc_back_ups_xs_1300_manual.pdf
    • https://cdn.shopify.com/s/files/1/0428/7594/5126/files/wedepodedulidinik.pdf
    • https://cdn.shopify.com/s/files/1/0431/0846/6845/files/15240526362.pdf
    • https://cdn.shopify.com/s/files/1/0432/7122/5502/files/73571404787.pdf
    • https://cdn.shopify.com/s/files/1/0434/5351/3893/files/23422432846.pdf
    • https://cdn.shopify.com/s/files/1/0434/1815/7221/files/revolutionary_war_on_wednesday.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000066f0.bin
c98eb6b11876163d4f276c4627ef2daad02c80e455be6c66889a24ecbce0ec9a
pdf-font-stream PDF embedded font (sfnt) at offset 0x66F0 5720 bytes
font_01_sfnt_off00007a5b.bin
73d672dd153888d7651adf2ea347066350507c5c6d534f51f36fe897a6e0cc15
pdf-font-stream PDF embedded font (sfnt) at offset 0x7A5B 10084 bytes