Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0b492389fcb5f6e…

MALICIOUS

PDF

74.7 KB Created: 2021-05-01 15:10:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: e5cb181a00b3190a1a79288fc9f92288 SHA-1: c523d6a5002c667dc22c36c9c88f7ec088f52a2a SHA-256: a0b492389fcb5f6e9fab1c62102c110d4592324cadc5b1d237dce3fc8890cd44
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ClamAV and an ML classifier, exhibiting characteristics of a phishing lure. It contains an external URI and an SEO redirector link pointing to 'https://zajinet.ru/strik?utm_term=pe+design+10+video+tutorials', disguised as a free download for design tutorials. The document body is heavily obfuscated, preventing detailed analysis of its content, but the overall pattern suggests a phishing attempt to redirect users to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://zajinet.ru/strik?utm_term=pe+design+10+video+tutorials PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4505687/normal_6066e16921c2c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4392877/normal_5fc7793df2795.pdfIn PDF document text
    • http://all-gopro.com/is_cannery_row_open_coronavirusviboq.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485927/normal_6054821a5da78.pdfIn PDF document text
    • http://2220202.ru/persuasion_jane_austen_movie_1995x7how.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4529977/normal_6043194c5e006.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370267/normal_602d957e5acde.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4382429/normal_5ff63ac3b5269.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368984/normal_602a0defb86f4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478398/normal_6009da781be23.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408187/normal_606cc77f49986.pdfIn PDF document text
    • http://axecheat5.xyz/ap_music_theory_course_onlinelfz34.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490128/normal_606a96e907828.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379222/normal_604325bd6340e.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/0a31ea4d-9d7e-4fa8-be31-06015d4c4a84/jubasagesolanobizeke.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2aa3a04a-4090-45b9-8223-a40bce052e7f/94076678764.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/231e186d-aa73-4344-b30d-1afc81b771c6/felsons_principles_of_chest_roentgenology_a_programmed_text_a_programmed_text_5th_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b3bbbe1d-8a93-4f26-bac1-7edcaa6904e3/nancy_drew_movie_2007.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ef25d4a4-4d8c-47e8-bf70-7d306deb9fe6/how_to_fix_a_honda_lawn_mower_pull_cord.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/827bcc0b-e1ef-4f47-996c-780c632b520b/51010893210.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1b7f2525-c5fd-4385-9560-e901a09684e6/kademuvudej.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/162be7d9-3c68-422e-957a-9c5774442587/kenmore_elite_stove_not_working.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_off0000e461.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE461 5248 bytes
SHA-256: 0d7d2939529da10b826892753a0b41d51ebd4e43294077c839f84b38f5d8adf9
font_01_sfnt_off0000f657.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF657 11120 bytes
SHA-256: 403b3a75316c3002cd272688de8d81d8af6a71e5ff4e56721220df3bf02a4fca