Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4c83ce421164437…

MALICIOUS

PDF

56.9 KB Created: 2020-08-25 04:22:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cefbc9f075caec7520aff3c5115a5084 SHA-1: d62a3b583386959346270b43da12af691be460cd SHA-256: f4c83ce421164437ab7d4ef03bce542c92ad5e36882282ef5807d9354905d020
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains numerous embedded links, with one specifically identified as a malicious redirector. The document body, though partially corrupted, contains text related to 'computer skills exam questions and answers' and a URL that points to a malicious redirector. This suggests a phishing or scam attempt designed to lead users to malicious content.

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.ru/pify?keyword=computer+skills+exam+questions+and+answers
    • http://files.pastelsocietyofsoutheasttexas.org/uploads/1/3/1/4/131410234/sozodutodibulajo.pdf
    • http://files.ieleaders.net/uploads/1/3/0/7/130776718/45c35ab516bd.pdf
    • https://cdn.shopify.com/s/files/1/0431/2625/9876/files/north_andover_weather_report.pdf
    • https://cdn.shopify.com/s/files/1/0431/7711/5810/files/rukumuruzug.pdf
    • https://cdn.shopify.com/s/files/1/0438/6498/1664/files/chuck_palahniuk_snuff.pdf
    • https://cdn.shopify.com/s/files/1/0429/7572/3673/files/after_effects_free_cs6.pdf
    • https://cdn.shopify.com/s/files/1/0434/7258/4870/files/halloween_songs_piano.pdf
    • https://cdn.shopify.com/s/files/1/0431/0374/8263/files/lakunolilixulevu.pdf
    • https://cdn.shopify.com/s/files/1/0435/4303/6053/files/luforobijan.pdf
    • https://cdn.shopify.com/s/files/1/0433/2794/6904/files/35893075798.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/vasopamomakazemujavinis.pdf
    • https://cdn.shopify.com/s/files/1/0428/3593/5388/files/buxaw.pdf
    • https://cdn.shopify.com/s/files/1/0462/0658/2937/files/11263217677.pdf
    • https://cdn.shopify.com/s/files/1/0437/7539/3944/files/7th_grade_math_book_common_core.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_off0000a1aa.bin
48b05739bc1aa12de39ebfc7d739b48b893015d80e7d3d5035692c1ebb71e2d4
pdf-font-stream PDF embedded font (sfnt) at offset 0xA1AA 5360 bytes
font_01_sfnt_off0000b3d8.bin
f7c8c3ccc4c61961b2ab71ecc6ccd5a346b1aa55aa2785fbe5b4a13f1049cac8
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3D8 10340 bytes