Malicious PDF — malware analysis report

Static analysis result for SHA-256 23986a191cfa45d7…

MALICIOUS

PDF

71.9 KB Created: 2021-06-06 21:25:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: b5ef12c59e654aaada6369bcf92c1be4 SHA-1: 0a6631634653fd2a8164c067ac1a3a3684aedb4f SHA-256: 23986a191cfa45d783feeae1edf38ebd61bb33e3145c7649dac77e41685a32bb
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly indicate maliciousness, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external URLs point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://oniceh.ru/pbw?utm_term=pathology+test+list+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4425229/normal_604dcc1060630.pdfIn PDF document text
    • https://farunigi.weebly.com/uploads/1/3/4/7/134716297/7a1d585ce2e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385217/normal_605144bf4dc53.pdfIn PDF document text
    • https://fotobuwab.weebly.com/uploads/1/3/4/3/134368258/4811859.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447880/normal_604dc185e7a7b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446280/normal_600b1afa4d79a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454163/normal_604a5ccb3bb8e.pdfIn PDF document text
    • https://zixafozete.weebly.com/uploads/1/3/5/3/135349102/2122659.pdfIn PDF document text
    • https://gojolukok.weebly.com/uploads/1/3/4/4/134455450/tudajigexe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453908/normal_603d3ed5d86fd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375503/normal_6023f99482701.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495395/normal_602d4d537945f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385009/normal_606a1d2c9913b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457604/normal_5fc594dbd71aa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485457/normal_602cf39dd66b1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369162/normal_60096b6eec5f4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387702/normal_604d1440247c6.pdfIn PDF document text
    • https://nojevuxosat.weebly.com/uploads/1/3/4/3/134357696/6918313.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4402932/normal_60082194bc9d3.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/9dbc5d65-4a8f-49ec-bbf4-4ac35eb8e6aa/neliviwakeworuxifufofotaw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6f39b18b-d99a-44b3-b4e3-a393da908f35/how_do_i_become_an_eyelash_extension_specialist.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_off0000dd0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD0E 5308 bytes
SHA-256: b207b89ffc7ad9efc680dc3f07f9c2849e8bc750257ff1b2b2e7ec61ff0e370d
font_01_sfnt_off0000ef2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF2B 10440 bytes
SHA-256: 7e6310c024f383ae2b3e23a99e06fae49c1b1a642052dd006b5351f08d9e1dc0