Malicious PDF — malware analysis report

Static analysis result for SHA-256 636106d273fc7356…

MALICIOUS

PDF

68.9 KB Created: 2021-02-16 02:37:13 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 3b3bc8641b20756d853680e5f1279bdb SHA-1: ded2cc9772c9b8a5847e4756ba76bbd9361f48d4 SHA-256: 636106d273fc735625763a99c3590d8e6346ff0824bccd33d3450f8fd1bfbefd
126 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://crophysi.ru/wix?keyword=saunders+nursing+survival+guide+ecgs+and+the+heart PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4487419/normal_5fccd6b46bbf4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462035/normal_5fe03cf5bbc01.pdfIn PDF document text
    • https://kelebewo.weebly.com/uploads/1/3/4/3/134359650/dopeno.pdfIn PDF document text
    • https://xuxulavadimuxa.weebly.com/uploads/1/3/4/2/134234789/7b5d07fd04df20.pdfIn PDF document text
    • https://nusutaligufobam.weebly.com/uploads/1/3/5/3/135393176/pinaxevapoxafe_jobagisod.pdfIn PDF document text
    • https://wegakerovosa.weebly.com/uploads/1/3/0/8/130873826/rukupugulama_xutodur_jikoluj.pdfIn PDF document text
    • https://tulivugid.weebly.com/uploads/1/3/4/6/134607321/9adbe7f6ac7b01.pdfIn PDF document text
    • https://wakejowedab.weebly.com/uploads/1/3/4/5/134599651/jigakopadutu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459796/normal_5ffdd22747cc7.pdfIn PDF document text
    • https://jasoveloxera.weebly.com/uploads/1/3/5/9/135967924/banaza.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413456/normal_5fda6c38b38a5.pdfIn PDF document text
    • https://bewogataxatux.weebly.com/uploads/1/3/2/6/132695278/5fa091d06f07.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470985/normal_601f45e4d752b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4493266/normal_5fd281e35d14e.pdfIn PDF document text
    • https://ginugifugebiner.weebly.com/uploads/1/3/4/2/134234672/14b63ea66e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367302/normal_6025ec25c115b.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://topadut.epizy.com/mefefowu.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cef1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEF1 5364 bytes
SHA-256: f50e6fcec763d349debe5b404387443c2ecbab1c427fae4205e38f9f48942f07
font_01_sfnt_off0000e12b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE12B 11604 bytes
SHA-256: 2aa7a7ea4a29a127360a367c0b39ec45514680c16addfca03e3fad9be0874669