Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a0805d24210cd27…

MALICIOUS

PDF

65.0 KB Created: 2020-08-09 07:13:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e569aab7add3b381ec2260c592ac5af9 SHA-1: 6fa80f3361076f2cb87c8a95ee036324d67ccb4f SHA-256: 5a0805d24210cd27b0e626fb354b8d90103886ac7861b23e4806f1e4eec85fdc
154 Risk Score

Malware Insights

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

The PDF contains embedded links, with one pointing to a known malicious redirector. The ML classifier strongly flagged this PDF as malicious. The document body, though heavily obfuscated, contains the URL that is also present in the heuristic firing, suggesting a lure to a malicious site. The presence of numerous external PDF links, many hosted on Shopify, indicates a link farm used for SEO poisoning or distributing 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=anamnesis+fisioterapia+pdf
    • http://files.worknbusiness.com/uploads/1/3/0/7/130775634/9d4ac95b0af7b31.pdf
    • http://files.ameliasclosetfilm.com/uploads/1/3/1/0/131070688/pagebesaxa.pdf
    • http://files.oxfordresearch.org/uploads/1/3/1/0/131070751/06e30dd6288.pdf
    • https://cdn.shopify.com/s/files/1/0438/2271/0941/files/bobazijabutowuwoku.pdf
    • https://cdn.shopify.com/s/files/1/0428/4094/8892/files/9596034559.pdf
    • https://cdn.shopify.com/s/files/1/0436/1981/1490/files/abraham_maslow_hierarchy_of_needs_theory_of_motivation.pdf
    • https://cdn.shopify.com/s/files/1/0429/0058/6649/files/93161120570.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/1741554469.pdf
    • https://cdn.shopify.com/s/files/1/0435/5316/1367/files/62102509469.pdf
    • https://cdn.shopify.com/s/files/1/0434/3853/8904/files/83740456408.pdf
    • https://cdn.shopify.com/s/files/1/0428/4035/9068/files/17993621177.pdf
    • https://cdn.shopify.com/s/files/1/0430/4705/9607/files/diwabewerulizivebikovugar.pdf
    • https://cdn.shopify.com/s/files/1/0428/4930/4732/files/best_book_to_learn_english_speaking.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/52299098946.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_off0000c2b4.bin
4a335fc4717b5867d9c98c031722b6d4fbbb104eb42afd18e9cdbe2f20fa5e47
pdf-font-stream PDF embedded font (sfnt) at offset 0xC2B4 5144 bytes
font_01_sfnt_off0000d421.bin
b62b844621be06bfab4c526d4beea6a9e387d54ef8b811dd55699b9e5fc71626
pdf-font-stream PDF embedded font (sfnt) at offset 0xD421 10336 bytes