Malicious PDF — malware analysis report

Static analysis result for SHA-256 667da7e54a59fd36…

MALICIOUS

PDF

82.9 KB Created: 2021-04-19 17:54:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 0df4827e104952559b50045fcc917c33 SHA-1: 23974cef14fa92bea4574e71920bba0d556373b2 SHA-256: 667da7e54a59fd36dea3c382c0d5047129573f35224c5890d60402ded5f0fb83
226 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable domains and suspicious URLs, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded URLs and the PDF's structure, which includes what appears to be obfuscated content, are indicative of an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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 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.
  • Image-heavy PDF with invisible link to suspicious domain high PDF_SUSPICIOUS_LINK_LURE
    PDF is a small image-heavy lure with invisible link annotations that send the user to a suspicious high-risk-domain URI. This matches credential-phishing carriers where the visible document is only a prompt and the real collection flow happens on the linked website.
  • 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://jottigo.ru/strik?utm_term=what+are+the+different+memory+partitioning+techniques PDF link annotation
    • https://cdn.sqhk.co/noperizapewo/gciiHge/65468105816.pdfIn PDF document text
    • http://vikiduxa.mywebcommunity.org/14284047910.pdfIn PDF document text
    • https://cdn.sqhk.co/nomuzali/NjWhijg/ginononemipawuvobur.pdfIn PDF document text
    • https://cdn.sqhk.co/borefigux/jbiifij/21186639072.pdfIn PDF document text
    • http://lixebafevoku.mypressonline.com/biomechanics_and_analysis_of_running_gait.pdfIn PDF document text
    • https://cdn.sqhk.co/jurugaguvedu/hiwCrhe/77450463638.pdfIn PDF document text
    • http://reawolt.online/pajafepumiketuvemu3ypk.pdfIn PDF document text
    • http://bitcoinlearningcentre.online/15660713777rj5bm.pdfIn PDF document text
    • http://boomua.site/shaolin_kung_fu_animal_formsq7x1x.pdfIn PDF document text
    • http://prizinsta.site/animal_farm_novel_in_urdu56t8m.pdfIn PDF document text
    • http://securitycheckingbrowservkcom.xyz/elementary_geometry_for_college_students_downloadufoqd.pdfIn PDF document text
    • http://5dradio.ru/934697616428l6v7.pdfIn PDF document text
    • https://cdn.sqhk.co/xasakeza/Ccic4gH/nulorakejikilekanofej.pdfIn PDF document text
    • http://sagunutu.medianewsonline.com/tenses_rewrite_exercises.pdfIn PDF document text
    • http://fikebek.sportsontheweb.net/12973116296.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/43dc4bea-b103-4d96-a543-9f50a24d1173/buxeganijimofipije.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b5ffa56c-4be4-42f1-a1f5-cd9fc7db8d55/hp_photosmart_d110a_ink.pdfIn PDF document text
    • https://8b83d164-5e56-46cc-b941-48f48810ddf3.filesusr.com/ugd/76ce43_a606de4673be4e19b9a5643dd9ee96fc.pdf?index=trueIn PDF document text
    • https://f95bebf3-6e70-44a0-a435-e8b8729243a1.filesusr.com/ugd/f34823_4c9bce8b0b6e4dabb552e6eb96be63b6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b5b66da9-c9ef-4663-ae8d-ca7965a2fa47/wim_hof_method_overview.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/049e92cc-ccc3-4233-aeaa-595e6bdb0860/o_que_a_poluio_da_gua_pode_causar_aos_seres_humanos.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_off0001046c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1046C 5780 bytes
SHA-256: c1422a66a199ddec2db3b7401c261eb2f5c9bafd64c2829fd983a627d45d7a9c
font_01_sfnt_off000117fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117FD 11116 bytes
SHA-256: ef2357e3bc00feaa885df7ea37398c5413f40bd006e58ba0ce3eca789f03b60c