Malicious PDF — malware analysis report

Static analysis result for SHA-256 36f9b3d85e654fd6…

MALICIOUS

PDF

62.2 KB Created: 2020-08-15 13:32:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fbac615232b228b2502ddcf7de7d5a85 SHA-1: 435d952b866ada4a01f3f4ba02ea18a25b93a509 SHA-256: 36f9b3d85e654fd634ec01be3356d45d5f3c1e72f61e727eea70347f25d2fa13
152 Risk Score

Malware Insights

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

The PDF contains numerous links, including one pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'SQL interview questions' and a URL that appears to be a lure for downloading a PDF. The heuristic firings indicate the PDF is a malicious redirector and part of a link farm, suggesting a phishing or social engineering attempt to drive traffic to malicious sites.

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.com/wb?keyword=sql%20interview%20questions%20for%20experienced%20professionals%20pdf%20download
    • http://files.cls-asia.net/uploads/1/3/1/4/131483009/gojovopitovofowolit.pdf
    • https://cdn.shopify.com/s/files/1/0433/2496/5019/files/libezavuzubazowuzazovike.pdf
    • https://cdn.shopify.com/s/files/1/0428/6647/5174/files/tusutufavime.pdf
    • https://cdn.shopify.com/s/files/1/0431/8350/5562/files/91502433237.pdf
    • https://cdn.shopify.com/s/files/1/0439/8107/8686/files/fafiliwamofolubur.pdf
    • https://cdn.shopify.com/s/files/1/0431/8635/6375/files/guwumomolotitixudawobozeb.pdf
    • https://cdn.shopify.com/s/files/1/0427/7056/3239/files/free_timesheet_calculator_australia.pdf
    • https://cdn.shopify.com/s/files/1/0433/6769/4501/files/xikefulewuxuliv.pdf
    • https://cdn.shopify.com/s/files/1/0430/3863/8241/files/worisu.pdf
    • https://cdn.shopify.com/s/files/1/0432/1335/7214/files/papusa.pdf
    • https://cdn.shopify.com/s/files/1/0439/6145/0654/files/12049137988.pdf
    • https://cdn.shopify.com/s/files/1/0430/8815/0690/files/eosinophilic_oesophagitis_guidelines_uk.pdf
    • https://cdn.shopify.com/s/files/1/0428/4855/1068/files/gifutalunapolupamoduf.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_off0000a081.bin
f33a03db6ded724f4ee0b0cd9eebb454403b980990de12fced77c955501302b2
pdf-font-stream PDF embedded font (sfnt) at offset 0xA081 5480 bytes
font_01_sfnt_off0000b341.bin
728e0c8eb6b960b346c1a798ec68147f531c245b6c0d94d00202bd81e888f5f6
pdf-font-stream PDF embedded font (sfnt) at offset 0xB341 13128 bytes
font_02_sfnt_off0000dcff.bin
1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCFF 4324 bytes