Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdacb12e532859f5…

MALICIOUS

PDF

40.4 KB Created: 2020-08-18 19:47:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e5ea6f5ff9e719349e8e4b3ae1ac436f SHA-1: 62c86ffa2fa8d80dda6bf5ffa9de144f2192c540 SHA-256: fdacb12e532859f5e7bba37fc9c2524595d78c4c9a016dc6888a4a22775f32cf
154 Risk Score

Malware Insights

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

The PDF contains a link disguised as a "Microsoft machine learning algorithms cheat sheet" that redirects to a malicious URL. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK confirms this behavior. The document body itself is heavily obfuscated but contains the malicious URL, indicating a lure to redirect the user to potentially harmful content. The presence of numerous other PDF links suggests a link farm strategy to improve search engine ranking for 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.cc/pify?keyword=microsoft+machine+learning+algorithms+cheat+sheet
    • http://files.randirouge.com/uploads/1/3/1/4/131408537/7877400.pdf
    • http://files.summerfoxart.com/uploads/1/3/0/7/130776082/vudidaniwenirid.pdf
    • https://cdn.shopify.com/s/files/1/0434/9899/5864/files/rolapemevokujudal.pdf
    • https://cdn.shopify.com/s/files/1/0434/6930/8061/files/3891192071.pdf
    • https://cdn.shopify.com/s/files/1/0430/6396/7906/files/87950619898.pdf
    • https://cdn.shopify.com/s/files/1/0437/4164/2906/files/wujalisixinepu.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/54729765263.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/gerakofidasetivivirodipel.pdf
    • https://cdn.shopify.com/s/files/1/0429/2083/7279/files/gunolimetejekosowosizopul.pdf
    • https://cdn.shopify.com/s/files/1/0431/8189/9944/files/fexilapuxabefokagisipe.pdf
    • https://cdn.shopify.com/s/files/1/0431/0538/6647/files/78562288109.pdf
    • https://cdn.shopify.com/s/files/1/0430/5548/0981/files/bohemian_rhapsody_piano_4_hands.pdf
    • https://cdn.shopify.com/s/files/1/0435/5804/3797/files/sell_5th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0427/8085/2383/files/active_passive_exercises_mixed_tenses.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_off00006116.bin
300095eb9cef4fc2cc3145bf2fa30392ec841626b125b867e8b70df822aad8a1
pdf-font-stream PDF embedded font (sfnt) at offset 0x6116 5300 bytes
font_01_sfnt_off000072f8.bin
02d7cc8dbb09900f7b51056bea14ed7dc07ebc350189a4ad80107a491943190f
pdf-font-stream PDF embedded font (sfnt) at offset 0x72F8 9852 bytes