Malicious PDF — malware analysis report

Static analysis result for SHA-256 af68079c57b921dd…

MALICIOUS

PDF

82.7 KB Created: 2021-04-05 01:06:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: cbfac60d9b197fe1e08ee6a19dbd50bc SHA-1: d9b6346d633ff4ff3daa0080f9674399f1c3c00a SHA-256: af68079c57b921dd5afe3e68a51e000f140753e15ef40890ceb9135cc9c94c59
196 Risk Score

Malware Insights

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

The PDF contains numerous external links, with one identified as an SEO redirector for 'free-download phishing'. The primary malicious URL, https://kuzutuzo.ru/strik, is likely used to host or redirect to a malicious payload. The ML classifier and ClamAV detection strongly indicate malicious intent, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • 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 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://kuzutuzo.ru/strik?utm_term=how+to+do+easy+origami+flowers PDF link annotation
    • http://rubisteq.online/d-link_dcs-932l_driver_download8xi9e.pdfIn PDF document text
    • http://matras-24.ru/how_to_support_autistic_child_in_schooluccd5.pdfIn PDF document text
    • http://alkim.xyz/danby_kegerator_dkc645bls_manualtalsv.pdfIn PDF document text
    • http://edaruzal.xyz/25097930496sis7l.pdfIn PDF document text
    • http://reduslimitalia-official.site/468316243200njln.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://28a90398-13b1-4b58-b54c-ed045a6bddf2.filesusr.com/ugd/7e9e1f_8e76b191346c449bb0d3ba30d66895a3.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/vebogotexaf/vocal_play_eng_sub.pdfIn PDF document text
    • https://s3.amazonaws.com/megodipewukitoj/qlikview_12_tutorial.pdfIn PDF document text
    • https://s3.amazonaws.com/dobesogum/73160558429.pdfIn PDF document text
    • https://s3.amazonaws.com/fefurorobumi/fujigisi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3ddfb260-f12e-4595-b075-184f35c1720e/nanostation_loco_m2_firmware_downgrade.pdfIn PDF document text
    • https://s3.amazonaws.com/juwofuxufijup/pichuva_kathi_tamil_movie_hd.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/508a0340-7b37-45a2-b774-536834925498/how_many_questions_are_on_the_texas_master_electrician_exam.pdfIn PDF document text
    • https://s3.amazonaws.com/wanasuvedigo/bujifopixurasu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c81b4b1-5abb-4337-b501-b26bcd43f68b/82086330759.pdfIn PDF document text
    • https://s3.amazonaws.com/novipaliwid/car_tire_size_guide.pdfIn PDF document text
    • https://0e098354-e5d1-4afc-9be7-763a70ae5e44.filesusr.com/ugd/ef253e_a9f689b887724dd68212b5975d99b93b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/607df693-88fe-4e10-99f6-1af6d40544f2/do_african_wild_dogs_eat_giraffes.pdfIn PDF document text
    • https://s3.amazonaws.com/fakuguvil/kepuxomefalofaja.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ea8fef5b-0dea-4406-ad96-a2cbcbca600e/47263410870.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a2b9e825-021a-4446-aad3-10930218489a/95292467650.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f6d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6D0 5064 bytes
SHA-256: 6aa8d5725ac01f9784e263094143c8684bc85c6b8b1996e6edf9d7ba60541156
font_01_sfnt_off00010821.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10821 11104 bytes
SHA-256: 80dbb62310dc8bad8dd583d93708d3a6ffcaad8529d9e94a11b03941a7630328
font_02_sfnt_off00012e0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E0D 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361