Malicious PDF — malware analysis report

Static analysis result for SHA-256 31bb53c1c5e62dd9…

MALICIOUS

PDF

84.2 KB Created: 2021-06-30 16:21:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 173b9fabbd1801ae97fbfd871e914667 SHA-1: 685722a0ca2f07caefe9d62d424e593dda3e2dba SHA-256: 31bb53c1c5e62dd9d011343e5e18105af33f180936bd1d5736e934d5e86a0136
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm, with many URLs pointing to compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. The file's structure and numerous external links suggest it's designed to redirect users to malicious content, potentially exploiting vulnerabilities in their browsers or applications.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/7eb338f3a3f51b545a1ce30ca2b5051c/kedobumesoxaseze.pdf
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/1a6f98e964e937ab6a534e350a469756/paseruvekexaf.pdf
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1607b4cc8d4c64---2936025675.pdf
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/bdd5f100a3e2164e8ed30ae305db0987/baxal.pdf
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/d8f9d728ec05c8306f34c28c26ad6195/34112311241.pdf
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607432d032bce---16566116920.pdf
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/1627e4c098a2586e58709392d7a18add/wotiwu.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/33u8dekut2hjq157ene7nvfqi3/25541877887.pdf
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/ab31fb717fcdd1c0fe64889d607acfd1/92317700631.pdf
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c027a47b8ff---54742211645.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ef73ecd647---116592249.pdf
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160cb8d1900d3c---repekinogofiw.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/77916ea9aeba64aca8d7591700e64bf4/fuzevum.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/9r3i35f7msq6epeda9jehm2tij/wikodaxesazavexan.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a08d5c11a38---84747931420.pdf
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac9e9d37921---juzedemetivarusosibek.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16096cbcc7613c---83783231551.pdf
    • https://www.herewardcarpets.co.uk/wp-content/plugins/super-forms/uploads/php/files/25fqbbogu5bmf5fhanqu1e97dc/gopamobanemi.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/35679cc52ac1b92aecf2d1f45fb37dd2/73698041028.pdf
    • http://clair-environnement.eu/catalogue_dynamique/file/46683879372.pdf
    • http://augustaelectricalwork.com/editorData/file/523387594.pdf
    • http://lacyfamilyunity.com/clients/2/20/203fd950dafdada58ea32e7b96f0d147/File/zunodolitikim.pdf
    • http://bestbuyfromindia.com/userfiles/file/fakitiruv.pdf
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/e0e265efe6ece3812a16c26e733ed6ae/62233534157.pdf
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/f474d904cae6d71511a0d22d9bf536e5/46449624026.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=c+reactive+protein+in+arabic
    • 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_off0000e6b2.bin
dbd9ffc4ac861f8c83c35aef371abf78e830fb713c34a74c5283699a14240e35
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B2 10392 bytes
font_01_sfnt_off0000fe23.bin
ca4b670f97346cb70cf50912f1978c3a5bec358b1c389fae1576a9817cc7817b
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE23 17436 bytes
font_02_sfnt_off00012bbe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12BBE 16792 bytes