Malicious PDF — malware analysis report

Static analysis result for SHA-256 99d3f2f2be94802f…

MALICIOUS

PDF

41.3 KB Created: 2020-08-14 22:18:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d3bd133880219fcc0d720af84197ef6d SHA-1: ea53cce2bef77a3038a8aa862ec9a4e967f87624 SHA-256: 99d3f2f2be94802f5d3c25d76af197741b09f5cb96fe4a34949d153adb3628ee
152 Risk Score

Malware Insights

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

The PDF contains embedded links that are part of a link farm, with one critical link pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'Cognizant interview questions and answers for freshers' and a URL that is also present in the heuristics as a malicious redirector. This suggests a phishing or social engineering attempt to redirect the user to 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=cognizant+interview+questions+and+answers+for+freshers
    • http://niruverer.pershoretownplan.co.uk/uploads/1/3/0/9/130969873/ef24e8d4c3d7c.pdf
    • https://cdn.shopify.com/s/files/1/0437/1932/7896/files/usssa_baseball_rules_2020.pdf
    • https://cdn.shopify.com/s/files/1/0428/6929/3215/files/puxubulibakowi.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/32150460784.pdf
    • https://cdn.shopify.com/s/files/1/0439/4264/1832/files/devaxiraluzosiz.pdf
    • https://cdn.shopify.com/s/files/1/0431/8298/1281/files/raladib.pdf
    • https://cdn.shopify.com/s/files/1/0432/0644/3176/files/zijonusabixuxilebuvewapa.pdf
    • https://cdn.shopify.com/s/files/1/0428/2934/9030/files/dozopavapavad.pdf
    • https://cdn.shopify.com/s/files/1/0440/4084/7510/files/treble_clef_ledger_lines_worksheet.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/25696514874.pdf
    • https://cdn.shopify.com/s/files/1/0428/8184/3353/files/squeeze_casting_process.pdf
    • https://cdn.shopify.com/s/files/1/0435/9149/9935/files/fexobigipobudet.pdf
    • https://cdn.shopify.com/s/files/1/0431/3314/1149/files/46976161498.pdf
    • https://cdn.shopify.com/s/files/1/0429/6487/7471/files/80698954526.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_off0000623e.bin
ffadf661cb5080ab26e0134578b58ca7724d2e1413783ea8dbcd003e76d3be30
pdf-font-stream PDF embedded font (sfnt) at offset 0x623E 5372 bytes
font_01_sfnt_off00007494.bin
33f52485ff012ad04d0e68299ec1f48668dbfef767f826325aa800bfc9f50f0d
pdf-font-stream PDF embedded font (sfnt) at offset 0x7494 10472 bytes