Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a64ada78919e46c…

MALICIOUS

PDF

85.0 KB Created: 2021-09-20 06:30:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1d0ceeda1d30e7c9fe1d068f5d76ea73 SHA-1: c0499da81c92f7be9689a956cb8d3fb1b6015c43 SHA-256: 8a64ada78919e46c618302240dd9b3e92ecfce56430632b01c5d963204ecc22c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm with numerous URLs pointing to other PDF documents, many hosted on disposable or potentially compromised domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of external URIs and link farm heuristics suggests an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 http://studiotipaldo.com/userfiles/files/60922811791.pdf In PDF document text
    • http://hastensandbreakfast.nl/userfiles/file/56370514220.pdfIn PDF document text
    • http://lammermoor.net/imagenes/file/vobagulodogamuwow.pdfIn PDF document text
    • http://lpkgoodframeupvc.com/userfiles/files/rolutapiludeki.pdfIn PDF document text
    • https://stpatswatertown.org/ckfinder/userfiles/files/80170117068.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145038e512ca---nafetetakimaso.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d455fd3d1c---jukolabibatan.pdfIn PDF document text
    • http://surtek.biz/image/files/20150405_054848.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/l770gencgpeb7f7pb3m5ah7kho/67782648979.pdfIn PDF document text
    • https://www.ewdel.cz/ckfinder/userfiles/files/dedikolodaleruwosidunota.pdfIn PDF document text
    • http://st03.it/userfiles/files/bisepoj.pdfIn PDF document text
    • https://globalmediaminds.com/uploads/files/22113924936.pdfIn PDF document text
    • https://elemental-ia.com/userfiles/file/65265766832.pdfIn PDF document text
    • http://tsrmmessina.it/userfiles/files/41300656427.pdfIn PDF document text
    • http://chuabenhxuongkhop24h.com/images/files/21452838306.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/ae40de8fbeee3e01de002436e0ce99da/duzomozozunemijiwo.pdfIn PDF document text
    • http://sun-apartments.pl/data/pages/lifovewoditab.pdfIn PDF document text
    • http://maidichike.com/upload/files/zogofulijoweduvumopiso.pdfIn PDF document text
    • https://rrrc.us/userfiles/file/50805028558.pdfIn PDF document text
    • http://restokrat.info/userfiles/file/rutumafureduzivabixit.pdfIn PDF document text
    • http://branonperformance.com/ckfinder/userfiles/files/bobujadatopedodegoxonubew.pdfIn PDF document text
    • http://phunggia.biz/userfiles/file/87759356794.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=persuasive+writing+words+and+phrasesPDF link annotation
    • 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_off0000e581.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE581 18360 bytes
SHA-256: 12c082cb00bbbf5e5105e3fb29c6954214efc1ddcad9abd61d5dfe48ecf84572
font_01_sfnt_off00011526.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11526 10880 bytes
SHA-256: 58012a416d01c8807e49d61551b2cbc293c67c527b7015be6d6d9f583c65f0d1
font_02_sfnt_off00012e22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E22 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1