Malicious PDF — malware analysis report

Static analysis result for SHA-256 31dbce9ac49b711f…

MALICIOUS

PDF

80.8 KB Created: 2021-08-15 01:18:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-25
MD5: eab7fd4943fcbe536587950747be0e71 SHA-1: 29b8760e897dd4796055471400815ef0aa11cc10 SHA-256: 31dbce9ac49b711fa677f36444eebeeeefc7d979ddb441e75f95eb22b4dab1e3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://roofmed.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a760ef45e33---19625491512.pdf In PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/f6c2fdf0fc1b566e60556c3c5f2c7336/sodawuxubimatubowejezux.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/638e4fdc7l0sn2jil59qnocoo0/xufira.pdfIn PDF document text
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d76fd42b34---78660074198.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b958ca077e3---zirufexorim.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/1610080c2f239a---jupara.pdfIn PDF document text
    • http://happyhanool.com/ckupload/files/dolebulufujavoperukuniga.pdfIn PDF document text
    • https://vico-inmobiliaria.com/ckfinder/userfiles/files/16480341946.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/1v770a5dbeoiqe6u3o318nt9g1/suveberudisobuzefavix.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/e24db48fa7cdb7f3f903e68398cae314/riwupirizokupili.pdfIn PDF document text
    • https://www.medicalbi.com/ckfinder/userfiles/files/nanuvunegokorenuxemofal.pdfIn PDF document text
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/33ff09259113b416aaded121b92f5c7c/74802672668.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16082637a84906---60379266251.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b5f08390c28---juzofaxuwedibekewadezulo.pdfIn PDF document text
    • http://strap.sk/uploads/files/patudilofexedezamu.pdfIn PDF document text
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/3fff3bf792bdde27ca7ca87e794eeaa6/72498619790.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160752262d74a1---79522313530.pdfIn PDF document text
    • https://fibaquitaine.fr/cebatrama/userfiles/files/toramozenomezolaliratun.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1609b2ca70b1b0---xagekawoloza.pdfIn PDF document text
    • http://fhhsclassof70.com/clients/4/42/42ce21dc30e429aa976ba070b22ccf93/File/41637470345.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/af7ed943569b6fd33229b4b5c6b1ada7/jiroliruniwib.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/sd53l7fn6lpsoevonstfgjb415/lofavipokuzawifebolal.pdfIn PDF document text
    • https://autopsrus.com/ckfinder/userfiles/files/95882193833.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/31c40827d5c40b4fb41d81b39a7e5051/pojalamobuzivulup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=decimal+to+binary+exercises+with+answersPDF 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_off0000d823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD823 10936 bytes
SHA-256: 58cccaba92539fb2210203f4871ae27e104b34025edbf37d7a4db144df927344
font_01_sfnt_off0000f15f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF15F 16936 bytes
SHA-256: 303b05fba0ea2603e968bf3e9379912aa51b36f507a22958632a807709de95ab
font_02_sfnt_off00011d6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1