Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ff15557ef854f8c…

MALICIOUS

PDF

94.5 KB Created: 2021-07-05 08:41:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 13764c6839e33ab5a2492a1be496b6d9 SHA-1: 02dd261f5b74c8a8a0b2daf07ec326fa0aa3bf0a SHA-256: 8ff15557ef854f8c3a51b84ce93e3c6e5c6391df65a2595ac5209df433ce205a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code or redirecting users. Several heuristics indicate the presence of link farms pointing to potentially compromised WordPress sites, suggesting an attempt to host malicious content or phishing pages. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://abogarestudio.com/userfiles/file/guxixujed.pdf
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/v3hcahfai88elpqj3i796rs2lb/zonur.pdf
    • http://aucoindeshalles.com/menu/file/25039449721.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607e3007422cf---41465513480.pdf
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/4cbac33bfab9858f2aa4d9ace43156b0/woxosirasedezarajanoj.pdf
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/b81ad16a2ad7eb5c2621165462b73cec/tixidozofozevedomijulop.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16089988b2653f---73559976389.pdf
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/4f4996a387a0c848c1a4bf8f1c0a7cee/rebinemojunuwexo.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b33b5ac5f3d---84762883322.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a967ab9fa4f---99811829249.pdf
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/081836d040711a0168706e42a061c50a/3100721643.pdf
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16076f47977aa7---romaretapiledabufizo.pdf
    • http://alphasigmaoverseas.com/userfiles/file/19550172323.pdf
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/c11fcf2957eb3ea63138319f8488fece/wewurawogobemorivaxed.pdf
    • https://minervatech.work/js/ckfinder/userfiles/files/pisade.pdf
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/jirt7hlk1utm984m6tiok77k6u/melikowokabosaxode.pdf
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/cqu6768mi3tdelb7u2kk46sj9k/tumufekigiwozajudari.pdf
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dff6083e6fa---sofikuteparubom.pdf
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607255797ebcd---95971862164.pdf
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/071883038d2dad021405dbe37abbc533/vivegaretuj.pdf
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/feb567f1554ce4e7965d92a8bacf5a95/bopalonitevabizirunesef.pdf
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/hg8tf01fv5uthen3lmdh2me5fs/xakagiruros.pdf
    • http://haozuowenwang.com/imagefiles/file/49607598974.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bc339a02f4f---55079031576.pdf
    • https://conexusinternational.com/ckfinder/userfiles/file/susuzusumogujinuku.pdf
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/e2e362f884c42e903d0a86441207d621/67506974559.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=advanced+structural+analysis+notes
    • 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_off00010a1b.bin
eebca8bb9411da5bfa927e165adf9f68c2f8aa43a21b248f45b07e05327a73ca
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A1B 10624 bytes
font_01_sfnt_off00012297.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12297 16792 bytes
font_02_sfnt_off00013aa9.bin
ed8ff868cf1cd7cf2540d16b086a7c4834227cc279756a727c86f7fabf1b808f
pdf-font-stream PDF embedded font (sfnt) at offset 0x13AA9 19164 bytes