Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef7f56fccb2350af…

MALICIOUS

PDF

83.0 KB Created: 2021-09-23 17:15:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8a4772168892f81afe3e7db1c7412ae1 SHA-1: 2b5a1f1f5743b0c778fbd690bc293151999bcb85 SHA-256: ef7f56fccb2350af5b4d889e8d7ab0fef9dda3240d0038c9ae511903ac79bf14
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to lure users to external resources. The presence of 'utm_term' parameters in some URLs indicates a potential phishing or tracking mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://drafthe.ru/uplcv?utm_term=last+installed+app+android PDF link annotation
    • http://www.recko.ru/ckfinder/userfiles/files/44919003736.pdfIn PDF document text
    • https://hujanuang.com/contents/files/rugububivax.pdfIn PDF document text
    • http://artgraf24.pl/userfiles/file/lilazofodanegizimeluwoli.pdfIn PDF document text
    • http://baocaosuhoatoc.com/luutru/files/98630272565.pdfIn PDF document text
    • http://rc-mst.com/mst/_upload/files/wukiroxawugu.pdfIn PDF document text
    • http://eltdb.com/UserFiles/files/sosolewatubefe.pdfIn PDF document text
    • http://chinawin-consult.com/userfiles/18888023799.pdfIn PDF document text
    • http://jumpinfit.it/userfiles/files/82649348283.pdfIn PDF document text
    • http://galeriejacqueselbaz.com/userfiles/file/89864551395.pdfIn PDF document text
    • http://macabrey-luthier.fr/data/Files/72386518334.pdfIn PDF document text
    • http://villabrown.it/userfiles/files/44482681220.pdfIn PDF document text
    • https://mundolibre.cl/uploads/userfiles/files/85351477921.pdfIn PDF document text
    • http://freestyler.cz/img/file/99162442238.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/7b964031b35fc5b62b65f188ce006f41/dufisatepibomegax.pdfIn PDF document text
    • http://debsecond.net/UserFiles/File/6491293295.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147c3a9a9638---vofafalebale.pdfIn PDF document text
    • http://webspace.mysdam.net/images/newsletter/files/ralapokimudibipezejaba.pdfIn PDF document text
    • http://haphadoor.com/upload/files/96402393382.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/repofojarilinesuravo.pdfIn PDF document text
    • http://www.ap-arte.ro/fckupload/file/89087040938.pdfIn PDF document text
    • http://topmebli.com/content/xuploadimages/file/xapito.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1613df48c12575---91795485033.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161481e53c42b5---tedokesivizuwumuwexa.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_off0000e11a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE11A 10344 bytes
SHA-256: 3a0b5f5e678f3534b18c165513f80dee32aa51b9e1b7d5b61051eda9888ca8ba
font_01_sfnt_off0000f87c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF87C 17820 bytes
SHA-256: 134f1f1ca76e219080cd86799fe16d94a551680ea2f80e609671fc164aa18083
font_02_sfnt_off00012678.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12678 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1