Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4c01287526428ff…

MALICIOUS

PDF

73.6 KB Created: 2021-06-26 14:16:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 06f97af62c1b2d6353bfb58c7f49cb98 SHA-1: 92bf4daee3eba213b9be8789d1ca701d7fac92b5 SHA-256: a4c01287526428ff9cb4cae3909214e17c0560e62f67c1b7abf228a99a7311d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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://inwebjor.ru/uplcv?utm_term=harsh+mohan+textbook+of+pathology+8th+edition+pdf PDF link annotation
    • http://www.sport-konyv.hu/userfiles/file/forokekesaguwariveku.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/83891349916.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b761bf82660---12240228181.pdfIn PDF document text
    • http://agrobud.net/uploaded/file/pubarovidoxipofu.pdfIn PDF document text
    • http://poorclarescork.ie/images/sewawoxametenagefonav.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9d25bef43f---91288063355.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a854f3aeae8---vadobuxusogujenawe.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/a0b6db5ba979c45b7d2d986afffcd5d8/vomoda.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099c6aa4d991---fakovavudezuz.pdfIn PDF document text
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/a9d113ff0d254dbd04031c5cce287970/16129146496.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b828d284097---42696555135.pdfIn PDF document text
    • http://geoodwierty.pl/files/file/pifiga.pdfIn PDF document text
    • http://relocationservicesgroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070aad288fd5---fesawibikapusi.pdfIn PDF document text
    • http://trendstyleimage.com/uploads/ckfinder/userfiles/files/79266157141.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/781b8ce1d86cc705378fc560525db922/xinipopu.pdfIn PDF document text
    • http://feuerwehrobrigheim.de/upload/files/28564480423.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609f8f28a3117---17971457276.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b66ee0219e0---44936283051.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160ad5f8bc2a6f---pekobizuzufat.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607746969792a---11379502794.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608417f83fb40---dekokifuzoguj.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16087b29546080---86970229796.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1607c000ded459---16264777032.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609a8d560f782---faposano.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bae3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBAE3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d2f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2F5 16160 bytes
SHA-256: 54bd0a6539750c6a05334a33b774be1ab4314fecc1c94bef6c6e3f0f5f6e2682
font_02_sfnt_off0000fc13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC13 11592 bytes
SHA-256: 77a1dcbac52553c1f528a878f19f25e75231872204fc29033fbdc5b8c1a1e07e