Malicious PDF — malware analysis report

Static analysis result for SHA-256 18c28a731dad816e…

MALICIOUS

PDF

101.3 KB Created: 2021-07-07 08:04:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 72047beb0f4c0c036cc19b73917f1ec6 SHA-1: 2fb4a11832012998a4e70f7b6d57325f1513a3c0 SHA-256: 18c28a731dad816e8dc385db5a59f253f9846c6b7a2ce126f081647e9085bb53
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous external URIs and link farm heuristics, indicating a strong intent to redirect users to potentially malicious websites. The ClamAV detection and ML classifier further support its malicious nature, classifying it as a phishing trojan. While no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to facilitate phishing or malware distribution by directing users to compromised CMS upload storage.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

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 https://crysiq.ru/uplcv?utm_term=neurology+history+and+physical+template
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16093aad4b5db6---47716405783.pdf
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/3fd8e8c450d820a3065860ba4f24cce7/81992669910.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a866b8ad8c0---62316684933.pdf
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bb61f02aafa---59840967535.pdf
    • http://quickvideo.nl/userfiles/file/5280257876.pdf
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160790b405a057---dopigegabobenusujelef.pdf
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/56058d017c29cf12cbfb2ab6c7d56ed7/jokamuvuxipaxedakojapuz.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607ca64d967be---68041713282.pdf
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/160897a182d055---lesaziwek.pdf
    • http://royalrep.com/userfiles/files/sidesetofo.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607eea72a2d34---wisili.pdf
    • http://cupta.org/userfiles/files/20210531032639.pdf
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f81c23f9d9---9912495914.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac6411e123---13096739870.pdf
    • https://hinodanang.com/uploads/image/files/69901386004.pdf
    • http://championshipsportsrings.com/clients/23492/File/91086110274.pdf
    • http://drapikowski.pl/uploaded/fck_files/file/bexurejasuxilotiw.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/453bee306a5b4b75ff8b552f11bc25de/tisanotubigi.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160787dc8219e9---67762467038.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f7a0c34bf---93265178859.pdf
    • http://webbuilders.com/files/file/49566068429.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/90836a7082a7787173c76c83189f3489/jodudofewovowe.pdf
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/6a3ba3d69e5e18bbf280f1d9e8e571df/bazavodugeru.pdf
    • http://irollee.com/userfiles/file/vidotanurodojeduviraroni.pdf
    • http://biotledlight.com/userfiles/file///15036160407.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_off0001275a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1275A 16792 bytes
font_01_sfnt_off00013f71.bin
7c934054e0ce2192dc48a31cc4daa47bfc4d104a61ab1f3d47459779d61b12cb
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F71 11152 bytes
font_02_sfnt_off00015922.bin
3d63177c5d550d74769c4fbb9dd899d8987a141fa6f1cf0e62cbcafcb231dd87
pdf-font-stream PDF embedded font (sfnt) at offset 0x15922 17192 bytes