Malicious PDF — malware analysis report

Static analysis result for SHA-256 91ba6ab5d039d09f…

MALICIOUS

PDF

44.9 KB Created: 2020-08-08 05:44:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e03ec4434ef2f85ba31e76a96b847ea8 SHA-1: e225b44db842d4eb9c74cfe4ab4547af0efc26c0 SHA-256: 91ba6ab5d039d09ff4356e4ee09804f8fed1bd187580b971d4b25ff7fc981391
154 Risk Score

Malware Insights

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

The PDF contains multiple embedded links, with one pointing to a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body is heavily obfuscated, but the presence of the malicious URL and the link farm heuristic suggest the primary goal is to redirect users to potentially harmful content. The document appears to be part of a link farm designed to artificially boost search engine rankings for 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.ru/pify?keyword=kingdom+animalia+phylums+pdf
    • http://files.beatrizgonzalezmusic.com/uploads/1/3/1/8/131856574/toled_zabesuvipiniraf.pdf
    • http://files.raquelmeraki.com/uploads/1/3/2/7/132740860/3354846.pdf
    • http://files.cynergy-tech.co.uk/uploads/1/3/0/9/130969399/waxoz_xutad.pdf
    • https://cdn.shopify.com/s/files/1/0428/4514/3206/files/benjamin_graham_o_investidor_inteligente.pdf
    • https://cdn.shopify.com/s/files/1/0431/7180/7381/files/opera_vpn_not_working.pdf
    • https://cdn.shopify.com/s/files/1/0432/6028/0982/files/xovasagetigazudutaxojoki.pdf
    • https://cdn.shopify.com/s/files/1/0448/1007/6321/files/active_and_passive_voice_notes_download.pdf
    • https://cdn.shopify.com/s/files/1/0437/2670/0696/files/37782997116.pdf
    • https://cdn.shopify.com/s/files/1/0427/3537/0407/files/65932487377.pdf
    • https://cdn.shopify.com/s/files/1/0432/5857/7046/files/wotisewokunupep.pdf
    • https://cdn.shopify.com/s/files/1/0431/0423/9770/files/nuxujajefiref.pdf
    • https://cdn.shopify.com/s/files/1/0440/3727/5813/files/wofazi.pdf
    • https://cdn.shopify.com/s/files/1/0436/5765/8521/files/comedia_de_calisto_y_melibea.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_off00006568.bin
4614c00efcbd08126c3356d89b9c990c4103b48b37f63580d4bdeb7cf16d907e
pdf-font-stream PDF embedded font (sfnt) at offset 0x6568 5112 bytes
font_01_sfnt_off0000769c.bin
1d1a9f6b75e052c68ccb1183c7f4cf0fe83717e674cdda9f7b52837bb36c4d42
pdf-font-stream PDF embedded font (sfnt) at offset 0x769C 10112 bytes
font_02_sfnt_off00009926.bin
0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333
pdf-font-stream PDF embedded font (sfnt) at offset 0x9926 4324 bytes