Malicious PDF — malware analysis report

Static analysis result for SHA-256 c52ec8c5fc7cfff8…

MALICIOUS

PDF

76.8 KB Created: 2021-03-08 09:36:29 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 273b39e1f2569ddeaf784a7ee445b1c0 SHA-1: cbc0773baad27dc50946703208bf1cd41e3fe4c1 SHA-256: c52ec8c5fc7cfff8b6a8fe6c9daa13a05d03e218134d851884311ce274443f37
244 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links pointing to various external websites, many of which are hosted on disposable domains or known redirector infrastructure. This strongly suggests a phishing or link-farming campaign designed to redirect users to malicious content. The ClamAV detection and ML classifier further support its malicious nature.

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
  • 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.
  • 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.
  • 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://yafferge.ru/strik?utm_term=correct+way+to+wear+mask+with+pleats In PDF document text
    • https://gaxasexafarud.weebly.com/uploads/1/3/4/5/134590452/ditoluzemuxekis.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366984/normal_601ba09801a0b.pdfIn PDF document text
    • https://cdn.sqhk.co/gadewekunel/shiIjiT/marco_vip_betting_tips.pdfIn PDF document text
    • https://dapalirodo.weebly.com/uploads/1/3/1/4/131483520/9251991.pdfIn PDF document text
    • https://xateboduf.weebly.com/uploads/1/3/1/4/131483383/rowuduw.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445733/normal_601b1d18e63db.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4410027/normal_5fe4b66c45373.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474736/normal_6016226384f00.pdfIn PDF document text
    • https://cdn.sqhk.co/rorezina/d8sjagh/bopitawepadadulem.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4452609/normal_5fe23841dbbfc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454042/normal_60434bf9e29e7.pdfIn PDF document text
    • https://cdn.sqhk.co/jasurisunav/bhjihgh/xiwofigu.pdfIn PDF document text
    • https://veworokog.weebly.com/uploads/1/3/1/6/131606039/dbb609b0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490369/normal_6009caa2d4c56.pdfIn PDF document text
    • http://hdvideo.design/what_is_the_relevance_of_technical_writing_in_the_business_worldxoj9k.pdfIn PDF document text
    • http://tvoeobrazovanie.fun/21669209854jv2gn.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4499636/normal_5ff01695c1d21.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/f7bbe6e3-53b3-44f5-bf23-9ee61130a861/16483461079.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4826ee5d-bf9b-48a5-8e8c-c55c75648027/zagegexuxix.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9bcd2c45-8f6a-4e0f-b7df-1783638d3483/why_does_my_smoke_alarm_keep_beeping_when_i_have_changed_the_battery.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f64466ee-98cc-4fa7-9b7b-1d81e602cc0b/91751779073.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_off0000f162.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF162 5336 bytes
SHA-256: e83fe67d1ddf90948c9b2862a88cfdef6cb4754ec76abdbc7b729d4d038e69d2
font_01_sfnt_off00010374.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10374 10028 bytes
SHA-256: 64c1fa71dd37e6f31ecded0412e305cf4e71c88aaa8387324db658baffa3f8bc