Malicious PDF — malware analysis report

Static analysis result for SHA-256 a654f584b9c8be0a…

MALICIOUS

PDF

88.4 KB Created: 2021-08-01 01:45:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ca3bb9c19a64de29c6f0eace6e2d55e5 SHA-1: 1836a5df482b0e6427cd6f5c1bdb847ae1694ac8 SHA-256: a654f584b9c8be0ae8c726ed9c9a1330c4049c761de5a9d240ec0016ea774c8d
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories, suggesting a link farm or SEO poisoning tactic. ClamAV and ML classifiers strongly indicate maliciousness, with the PDF being detected as a phishing trojan. The presence of external URIs and link farms points towards an attempt to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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
  • 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 https://mut-zur-veraenderung-hambuch.de/userfiles/file/16889059895.pdf
    • https://aonetreks.com/uploads/file/nixiremajosesiratufovudot.pdf
    • http://hb1004.com/userData/board/file/23257911460.pdf
    • https://ecodiagnost.com/ckfinder/userfiles/files/18836869026.pdf
    • https://bodymart.in/ckfinder/userfiles/files/wipesenekafige.pdf
    • http://carefirstwalkathon.com/clients/8/89/89514deb4c0e8807eb046cac28c4977f/File/48407184878.pdf
    • http://groupkaishan.com/d/files/15449059439.pdf
    • http://rund.cz/UserFiles/File/tuxazigotuxobe.pdf
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1609c34d5ca318---vabomukamizuridar.pdf
    • https://medicentrumnz.eu/medicentrum/files/file/89586396521.pdf
    • https://dakhoathienhoa.net/images/files/52152771082.pdf
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/nk0iahq4afu6ci52akssgrqei3/2029320564.pdf
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/g1l76bakdf44sqar2kltheu6po/78541903982.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a59e1d547ff---dukirulubulo.pdf
    • http://fields-on-earth.com/13111446519.pdf
    • https://www.pactforfamilies.org/ckfinder/userfiles/files/85596458559.pdf
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/81dc462d41e1545c092c9a8ed0c31038/2042880746.pdf
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/78b321220861567ac8952fb6d90623f3/bunafuzewonutugapufafop.pdf
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/5d020377439b0ee1056bb88b924b5376/birab.pdf
    • http://ccforum.kr/uploads/file/1621646963.pdf
    • http://centralgiving.com/media/userfiles/file/zevivukamiwujatixofukufe.pdf
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/58ce8d562e0be9dc3070b5434f3b5d57/zegitefibuk.pdf
    • https://www.cittadelmiele.it/wp-content/plugins/super-forms/uploads/php/files/db707a788250c476240e18a1eada5299/12366908545.pdf
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a74a214b130---dalonaratut.pdf
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c5f17eeaf01---54367773874.pdf
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e82dddb848---87174007683.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=fundamentals+of+anatomy+and+physiology+online+pdf
    • 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_off0000f26c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF26C 16792 bytes
font_01_sfnt_off00010a83.bin
60c580ecbc70829b4dfb9995b06e9eb570bad48e3fdb552386cb557e6a8801f6
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A83 11036 bytes
font_02_sfnt_off000123ca.bin
4b4d6f86d234a4c206d6eb8afb69f4752300623116ce6a475ae95b55bfb23dc2
pdf-font-stream PDF embedded font (sfnt) at offset 0x123CA 18036 bytes