Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f3aa2e1b8480a4b…

MALICIOUS

PDF

43.5 KB Created: 2020-08-26 10:48:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9a007541675ca4d50d5e308dcb44490e SHA-1: 6f6a7157e4eb07feed97f1d6369d15cb792f6b38 SHA-256: 5f3aa2e1b8480a4b4c4e948b536599896cb05858f04c73f64d4992204fc53c3e
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, many of which point to a link farm designed to redirect users to malicious infrastructure, specifically identified by the heuristic PDF_SEO_LINK_FARM. One prominent malicious redirector URL is https://ttraff.cc/pify?keyword=quadriceps+strengthening+after+knee+surgery. The ML classifier also strongly indicated maliciousness. While no scripts were explicitly extracted, the structure and embedded links suggest an attempt to trick users into navigating to harmful sites, likely as part of a phishing or malware distribution campaign.

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=quadriceps+strengthening+after+knee+surgery
    • http://suwopotub.trinidadrifleassociation.org/uploads/1/3/1/1/131164250/gozume.pdf
    • http://files.kinesiologyandcounselling.com/uploads/1/3/1/4/131438002/wudizelapu_gekilu.pdf
    • http://files.tulsalines.com/uploads/1/3/1/0/131069789/e487a295.pdf
    • http://files.greenrootsgourmet.com/uploads/1/3/1/4/131453588/26d064099ed1a50.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0438/6163/9318/files/bsc_number_theory_notes.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/tawoxusabevesumaxev.pdf
    • https://cdn.shopify.com/s/files/1/0429/0212/6755/files/mupoguwupedutulakajun.pdf
    • https://cdn.shopify.com/s/files/1/0436/7518/9401/files/80256057178.pdf
    • https://cdn.shopify.com/s/files/1/0431/0079/9140/files/44588360399.pdf
    • https://cdn.shopify.com/s/files/1/0431/5791/3754/files/kisamulugawe.pdf
    • https://cdn.shopify.com/s/files/1/0434/4492/8674/files/ketuzebejiwotetazinemu.pdf
    • https://cdn.shopify.com/s/files/1/0434/4555/1256/files/93941037469.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006a81.bin
33719fc84cdb85ffa58e2f10993e56519baaf918cc57d2d33e1b938db28e65e5
pdf-font-stream PDF embedded font (sfnt) at offset 0x6A81 5612 bytes
font_01_sfnt_off00007d9a.bin
6958eedfddfd324935bef84c8a1beb7b3191598acb9705d7b487ea42d2a2ea6a
pdf-font-stream PDF embedded font (sfnt) at offset 0x7D9A 10516 bytes