Malicious PDF — malware analysis report

Static analysis result for SHA-256 8191c91514294278…

MALICIOUS

PDF

100.5 KB Created: 2021-09-06 17:35:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e98d159f1f9004ce8d13ed2a2c61de17 SHA-1: 47fbe4c886bddcbf390eb6c840abad659923eef1 SHA-256: 8191c915142942784ac916be55a01825416f34256db3f9c0c0247bdbb0e5605c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to other PDF files, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of external URIs and compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://infrive.ru/uplcv?utm_term=present+value+and+future+value+table+pdf PDF link annotation
    • https://selapro.com.au/application/third_party/ckfinder/userfiles/files/84285380259.pdfIn PDF document text
    • http://instit.ac/ckfinder/userfiles/files/tezijebarafisixedu.pdfIn PDF document text
    • https://thewaves.net/wp-content/plugins/super-forms/uploads/php/files/083le9l0gqf9cdgebu02ucdjju/fipewoxu.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160976961d8920---giginugizategazagu.pdfIn PDF document text
    • https://ruta.hu/ckfinder/userfiles/files/71757267736.pdfIn PDF document text
    • http://silesiacapital.eu/data/file/3365945331.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/0855854d67cacff00a371b84349ebe2e/14076107818.pdfIn PDF document text
    • http://sarljarry.com/userfiles/file/wuzozuwitisetanoliban.pdfIn PDF document text
    • http://www.ez4parcel.net/upfile/files/2021/08/09/pitenojovaviva.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a4646b24901---lixogijojavofefatiwojen.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/16e89e1d97374a33c25f983325a4d208/63682760120.pdfIn PDF document text
    • http://bippex.com/filespath/files/20210815124937.pdfIn PDF document text
    • http://swissies.lt/ckfinder/userfiles/files/fegokejumuturevas.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/ue4t09g3d09jgq7pqefd3rjqh8/nuvoweruwikavaluwaze.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/57657v5amgceh3ij0tcnflu3hk/jidemuvovabupe.pdfIn PDF document text
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/160804fc5dd309---7913810365.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/161010759885df---lizexoj.pdfIn PDF document text
    • https://rts-wm.com/ckfinder/userfiles/files/sexefijozapuwegagolo.pdfIn PDF document text
    • http://ottotech.center/userfiles/file/tejusanapat.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160f595af3317b---sobuv.pdfIn PDF document text
    • https://gastrotest.co/ckfinder/userfiles/files/33051662773.pdfIn PDF document text
    • https://journeywithmypet.com/ckfinder/userfiles/files/840417856.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081efbf34490---22706857154.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/666b0929398897f08f6fe0151ddb3c44/tofisituriwozejapije.pdfIn PDF document text
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/19884bd48ca97ecd24a443406c8d3596/zopaluzukuviposujipep.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_off000123d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123D6 18212 bytes
SHA-256: 63e8ac72b85e2da78fecfa54c78a4f67eed4ba2459f3661b0f8c558bf581dbbf
font_01_sfnt_off000153b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x153B1 10588 bytes
SHA-256: f7316aa656c12703023fb69bd1350f7c814ec1372c03c230d82d53664d5bc22f
font_02_sfnt_off00016bd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16BD4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1