Malicious PDF — malware analysis report

Static analysis result for SHA-256 38d74b3c1a0a688f…

MALICIOUS

PDF

41.9 KB Created: 2020-08-17 16:01:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d651eca2a2288afcac9e098234d7b4b9 SHA-1: 77fd55e6a7580be4c08b131ee30188ae7a3438b7 SHA-256: 38d74b3c1a0a688f64dc72ebd4ca3f4c2022d616f7572442f6464481f1a0efe6
152 Risk Score

Malware Insights

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

The PDF was flagged as malicious by an ML classifier and contains a link farm pointing to a known malicious redirector. The document body, though heavily obfuscated, contains the URL that leads to the redirector, suggesting a lure to download potentially malicious content. The presence of numerous links to external PDFs, many hosted on Shopify, indicates a SEO-based link farm strategy to attract victims.

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=cacti-+0.+8.+8a.+exe+free
    • http://files.bsutransit.com/uploads/1/3/0/9/130968921/fitutisivubifowagi.pdf
    • http://files.alantong.com/uploads/1/3/0/7/130740477/4282330.pdf
    • https://cdn.shopify.com/s/files/1/0437/7575/4389/files/electronic_ignition_system_download.pdf
    • https://cdn.shopify.com/s/files/1/0429/3056/9382/files/87926784562.pdf
    • https://cdn.shopify.com/s/files/1/0428/8472/6943/files/sorujuk.pdf
    • https://cdn.shopify.com/s/files/1/0432/3429/5966/files/20814620890.pdf
    • https://cdn.shopify.com/s/files/1/0428/9075/6259/files/mesusatavoberuwisovovi.pdf
    • https://cdn.shopify.com/s/files/1/0433/8538/9206/files/caracteristicas_psicologicas_del_adulto_mayor.pdf
    • https://cdn.shopify.com/s/files/1/0429/0733/6867/files/xulewutewali.pdf
    • https://cdn.shopify.com/s/files/1/0432/5107/3174/files/angaraka_ashtottara_shatanamavali_in_telugu.pdf
    • https://cdn.shopify.com/s/files/1/0434/8713/3860/files/24110160797.pdf
    • https://cdn.shopify.com/s/files/1/0428/6296/8991/files/weight_gain_diet_plan.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000059ed.bin
caf5a3b3f91d35f70cf7180d860f507a931bffd3379377a4e7131a3e0ca3b2dc
pdf-font-stream PDF embedded font (sfnt) at offset 0x59ED 4728 bytes
font_01_sfnt_off00006a1b.bin
9dd42b0f26bac4338f2c45f61cf5d9b4c00d2ef869dc71ce51103e8cbc62b657
pdf-font-stream PDF embedded font (sfnt) at offset 0x6A1B 10212 bytes
font_02_sfnt_off00008d13.bin
b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c
pdf-font-stream PDF embedded font (sfnt) at offset 0x8D13 4324 bytes