Malicious PDF — malware analysis report

Static analysis result for SHA-256 c48bf57c8a3f4e8b…

MALICIOUS

PDF

49.2 KB Created: 2020-07-29 10:23:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d34f53e0805f2ef31143032288578b54 SHA-1: 5b8cd0afb57d31bf21b4928950436241a3338d8d SHA-256: c48bf57c8a3f4e8b0a144d27df9f58d1b67f623fa57ae55fdf6d3a12cb4f9f63
152 Risk Score

Malware Insights

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

The PDF file contains a document body that appears to be a lure for job aptitude questions, combined with numerous embedded URLs. One critical heuristic indicates that the PDF links to known malicious redirector infrastructure, specifically `ttraff.ru`. Another critical heuristic flags the PDF for containing a mass external PDF link farm, with `cdn.shopify.com` being a dominant host for these links. The ML classifier also strongly flagged this PDF as malicious.

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=wipro+aptitude+questions+and+answers+for+freshers+2020+pdf
    • http://files.royal-artstore.com/uploads/1/3/0/8/130874207/suvipiwifelur.pdf
    • http://files.impossiblefarmher.com/uploads/1/3/1/4/131410234/rinoxufu.pdf
    • http://files.kendralsaunders.com/uploads/1/3/0/7/130775471/folipikuzutixo.pdf
    • https://cdn.shopify.com/s/files/1/0428/9419/6902/files/jibenobuxome.pdf
    • https://cdn.shopify.com/s/files/1/0435/8435/6507/files/2808038449.pdf
    • https://cdn.shopify.com/s/files/1/0428/2118/9788/files/23371795726.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/69651331918.pdf
    • https://cdn.shopify.com/s/files/1/0433/9915/1768/files/fumalojugagobavo.pdf
    • https://cdn.shopify.com/s/files/1/0431/7026/7300/files/2750406587.pdf
    • https://cdn.shopify.com/s/files/1/0431/0849/9618/files/pelebu.pdf
    • https://cdn.shopify.com/s/files/1/0432/8351/3494/files/64761855058.pdf
    • https://cdn.shopify.com/s/files/1/0432/9888/1704/files/dubozegututumevodediril.pdf
    • https://cdn.shopify.com/s/files/1/0437/3161/5909/files/35727816955.pdf
    • https://cdn.shopify.com/s/files/1/0430/5525/1605/files/burafexudubatakomev.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/
    • https://cdn.shopify.com/s/f

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007fef.bin
8fae44bf610c88500371fab4b10c6109cee4188e542635311993d6b7e34bbb88
pdf-font-stream PDF embedded font (sfnt) at offset 0x7FEF 5484 bytes
font_01_sfnt_off0000929d.bin
5b90f8ede2d2f01d1663c21dd9c047a3f1486eaa43f7afc7488bc8f00fcf1ec6
pdf-font-stream PDF embedded font (sfnt) at offset 0x929D 10880 bytes