Malicious PDF — malware analysis report

Static analysis result for SHA-256 93f3551adf44d845…

MALICIOUS

PDF

81.5 KB Created: 2021-03-15 23:13:55 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 3242feb185c3ff81bd8c8e9b95afa13d SHA-1: 4430ec9db49192bd9674504991eac3636d9bcb11 SHA-256: 93f3551adf44d84594c290d6e038c1ea537366daf9eb8ed1670dc5d2a349d458
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of external links, many pointing to disposable domains, as indicated by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. ClamAV and ML classifiers also flagged the file as malicious, specifically as a phishing trojan. The embedded URLs and the nature of the link farm suggest an attempt to manipulate search engine results or distribute further malicious content, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://kuzutuzo.ru/wix?keyword=cmp3+grade+6+answer+key+investigation+4 PDF link annotation
    • http://uptodate.site/392583287076up8m.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384150/normal_602a3fb471d2d.pdfIn PDF document text
    • http://tesocoin.online/convert_to_jpg_size_200kbz4xin.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365542/normal_602ca2b89b669.pdfIn PDF document text
    • https://vubufogos.weebly.com/uploads/1/3/4/7/134766152/mewisenogivisewikit.pdfIn PDF document text
    • https://padamiraniz.weebly.com/uploads/1/3/5/3/135305831/tazalogin.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495849/normal_603d1c153dbeb.pdfIn PDF document text
    • https://bapizemu.weebly.com/uploads/1/3/1/1/131163962/cdc97e07f7e.pdfIn PDF document text
    • https://kukegogefip.weebly.com/uploads/1/3/2/6/132681459/cf9cbc55db73f4.pdfIn PDF document text
    • http://susojatafumo.22web.org/hp_spectre_x360_15_motherboard_replacement.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/95a8a3be-be72-47f0-a688-ade795f03640/75760882462.pdfIn PDF document text
    • https://07d68bf2-0661-47e2-9ffe-eae068a071af.filesusr.com/ugd/fef806_7b50bdfbc0a94c969050f9702c89c740.pdf?index=trueIn PDF document text
    • https://6afed14e-2b01-442b-8c2e-11a8a6f39965.filesusr.com/ugd/46a5ae_1e592ccfe14a492697a29e644acdd33b.pdf?index=trueIn PDF document text
    • https://63aa7d51-6c54-48cc-ac87-b710a0da19c3.filesusr.com/ugd/c8d394_b882cddaacf64e64aad55460297dbb3e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/7aad0875-3b5e-4ab1-af81-2c802258abb9/fozolisejemokogo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c4747f9c-e0ca-4093-91c4-5434a067ee51/en_la_mitologia_griega_los_dioses_del_inframundo.pdfIn PDF document text
    • http://xojixitutatafu.epizy.com/20373120488.pdfIn PDF document text
    • https://9005a25f-7293-4a73-bb0f-bc58e8c16807.filesusr.com/ugd/e3834b_61e5860c45c54208b2570e6fb4d4d39f.pdf?index=trueIn PDF document text
    • https://0502d5d0-a0f5-47b8-bc1c-644c46e4e431.filesusr.com/ugd/6cabbb_f732c702167d4368afbe3252fac0cdc3.pdf?index=trueIn 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_off0000ff8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF8B 5876 bytes
SHA-256: 7d7b041fbd165736856d02dcf482348569687d535d01b30af185edc5a51db30c
font_01_sfnt_off00011396.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11396 10944 bytes
SHA-256: 57a576230cab2f1bf1a5f069a675160613b13d72e6bfe6a6e8a1276ea266fd56