Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bcbc28ebef997e3…

MALICIOUS

PDF

82.9 KB Created: 2021-09-06 17:29:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 965c07d5e7fc05b9a88c131402140cf3 SHA-1: f895fcfaea7707125de3d290ca7e553465938979 SHA-256: 3bcbc28ebef997e39faf9205fe599336364e64b7cb1122ac0669dd2b5733d417
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of external URIs, many of which point to compromised WordPress sites. The ML classifier and ClamAV both flagged this file as malicious, indicating a high likelihood of malicious intent. The primary function appears to be acting as a link farm, potentially for SEO manipulation or to host phishing content, rather than executing a direct payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://cructi.ru/uplcv?utm_term=rondeau+mouret+piano+pdf PDF link annotation
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/dc46eec6a0d5d558f20838d4fe124af1/zodaxisawada.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16127434fd63d0---muvenirederasolenalim.pdfIn PDF document text
    • https://samoinstitute.mn/uploads/assets/file/55924803979.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/a6ed2658085e4903a802555a2e6b1a65/37492530781.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2273bf8ad---88603874436.pdfIn PDF document text
    • http://normandyclassof79stl.com/clients/e/e1/e16d7b8530e96d8d426d6b963c92b0b5/File/momepupodaremazudedut.pdfIn PDF document text
    • https://liur-krd.ru/userfiles/file/31385350845.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160976f916db4e---54283306948.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/99d4943acb3fb0119047eb7cd5faf3c8/92923703959.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/346721ca2ea2b47702806d9ab4f1d3ab/20291071986.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/94003938432.pdfIn PDF document text
    • http://pampa.be/uploads/userfiles/files/pejosilabetimi.pdfIn PDF document text
    • http://motocams.cz/ckfinder/userfiles/files/84873864528.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/66152349104.pdfIn PDF document text
    • http://biancoacolori.it/userfiles/files/17892978919.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b1812ee330---35403106767.pdfIn PDF document text
    • https://itandem.net/ckfinder/userfiles/files/54136118786.pdfIn PDF document text
    • http://blueyee.com/upload/file/241922335268.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/30297081510.pdfIn PDF document text
    • https://susta.vn/userfiles/file/widevikin.pdfIn PDF document text
    • http://neoneofytou.com/ckfinder/userfiles/files/bivalaruvegufox.pdfIn PDF document text
    • https://jvlegacyhomerepairsmd.com/nbloom/fckuploads/file/dotesogopojazerexo.pdfIn PDF document text
    • https://nhatngudongkinh.com/upload/ckupload/files/48900517259.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160aa67ef6a799---nogizeboridemekifuripuvug.pdfIn PDF document text
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/kumozuzefidofemefaje.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_off0000dc67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC67 18736 bytes
SHA-256: 7f62d06013c9fa6ff771aa713c75f48eeac1f7ae13790f89bbcc1116c677acd6
font_01_sfnt_off00010ded.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012604.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12604 10588 bytes
SHA-256: fba6cf129f8884e9f9541ee560997d9a2f84adefdb094a76717ef1719ac76574