Malicious PDF — malware analysis report

Static analysis result for SHA-256 829b8d892343c586…

MALICIOUS

PDF

90.1 KB Created: 2021-06-28 09:07:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bbc246823142d7f4b92e1d5935c8c233 SHA-1: 4d7d5d36176e8a9f43ae57c1d8f28c3e3557789d SHA-256: 829b8d892343c586cf3790d5b1cacf3e3f0816c4f7ef6b7b5a01746b9d3167dc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. Multiple heuristics indicate the PDF contains numerous links pointing to various domains, many of which appear to be compromised or disposable hosting. The presence of external URIs and link farms suggests an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://anhuizhkj.com/upload_fck/file/2021-5-2/20210502030117551541.pdf
    • http://samafb.org/uploadfilefiles/95564791737.pdf
    • http://vivo-mebel.ru/upload/file/27507282394.pdf
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5f32b04a2---tuvigojimorotojoreba.pdf
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/92c87fcb0cbd62e8987b23e2618875a5/95422868850.pdf
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a9c4890b3ba---4605519624.pdf
    • http://broadmoor80.com/clients/866172/File/kanapigaku.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088fabf7a350---79114720003.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16079b608f3f2b---29939122126.pdf
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8893da6f05---93438453925.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160adc382dd8c0---38609386996.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160d3b55fd62dd---53473657754.pdf
    • http://panziofabian.hu/fck_kepek/miwajulutusonewipuvizilo.pdf
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/1e8007fd2958220d02257edd9589fbad/zarapibusibikozotorug.pdf
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16074196eb8bd7---nigod.pdf
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/986em1dhfvgvftn6doh7736e51/81774517108.pdf
    • http://wib24-admin.de/uploads/file/84023112827.pdf
    • http://championsview.net/userimages/kaxidowatevuneluvosebi.pdf
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a8288293a6---35508416275.pdf
    • http://busangh.com/attfile/fckimg/file///2021061934355_659247962.pdf
    • http://sunnysolutions.it/uploads/assets/file/subofewukosolifu.pdf
    • https://steammining.com/userfiles/file/24149850116.pdf
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9eea4aa945---92961087631.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=leek+and+brussel+sprout+gratin
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fa5a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA5A 16792 bytes
font_01_sfnt_off0001126c.bin
5881b12c664646522fbe1e169c1704fc66744829071e281a508b48eeab6c4d53
pdf-font-stream PDF embedded font (sfnt) at offset 0x1126C 17660 bytes
font_02_sfnt_off000140d6.bin
d848a0b27ad07b43a3de02d3b5c910c8cc9f399af1dc5a952e9bd7c4dcf89721
pdf-font-stream PDF embedded font (sfnt) at offset 0x140D6 10856 bytes