Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f8b6d36f9791b4a…

MALICIOUS

PDF

51.9 KB Created: 2020-08-22 21:43:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2f22cadf8a82484f4ca0625603b2047d SHA-1: b6b6018ecda458b0319c1b2754a6947c63d9c497 SHA-256: 8f8b6d36f9791b4a87d9a40bf94929c4b43ca8a985dd3f2a000b91161a0b1d95
152 Risk Score

Malware Insights

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

The PDF contains a mass external link farm, with a primary link pointing to a known malicious redirector. The document body, though heavily obfuscated, contains the URL 'https://ttraff.cc/pify?keyword=case+study+questions+and+answers+in+management', suggesting a lure to a malicious site. The ML classifier also strongly indicated maliciousness.

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=case+study+questions+and+answers+in+management
    • http://files.hillcresteastpoint.org/uploads/1/3/2/7/132712080/5313812.pdf
    • https://cdn.shopify.com/s/files/1/0437/0402/5242/files/que_es_una_acta_constitutiva.pdf
    • https://cdn.shopify.com/s/files/1/0429/9322/1783/files/39057185038.pdf
    • https://cdn.shopify.com/s/files/1/0429/9912/0033/files/kefikotilanuvasixuvuve.pdf
    • https://cdn.shopify.com/s/files/1/0428/3380/5471/files/79806403681.pdf
    • https://cdn.shopify.com/s/files/1/0435/9107/3947/files/reaccion_alergica_a_picadura_de_abeja.pdf
    • https://cdn.shopify.com/s/files/1/0432/7663/2220/files/75931640943.pdf
    • https://cdn.shopify.com/s/files/1/0436/6503/1321/files/8meh_ru7jq_acdrm_mqepr_g3s23_fembr_aced.pdf
    • https://cdn.shopify.com/s/files/1/0430/2074/6906/files/nozesudaw.pdf
    • https://cdn.shopify.com/s/files/1/0427/9291/1007/files/gupudeguzomusovidufimed.pdf
    • https://cdn.shopify.com/s/files/1/0429/7365/9290/files/65445815943.pdf
    • https://cdn.shopify.com/s/files/1/0428/8780/7129/files/49548974902.pdf
    • https://cdn.shopify.com/s/files/1/0433/3027/3448/files/letimawukeda.pdf
    • https://cdn.shopify.com/s/files/1/0427/5650/5756/files/kagokafobujusivoladalevol.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_off00008c5b.bin
f91da70db47f29d072827bc40477fbe9e8daede72590bcf7b1bc40e78d12a99f
pdf-font-stream PDF embedded font (sfnt) at offset 0x8C5B 5340 bytes
font_01_sfnt_off00009e74.bin
4144f3e20219c585270444545e970ec8badf8d2eb52a192fd3d509358efd361d
pdf-font-stream PDF embedded font (sfnt) at offset 0x9E74 10524 bytes