Malicious PDF — malware analysis report

Static analysis result for SHA-256 8877609fb4fe55dc…

MALICIOUS

PDF

80.2 KB Created: 2021-09-07 01:00:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 32d1530fc34ee30eaee1071d85c7f65b SHA-1: 12022d645589b7f38ee219a16436fb575172c2e0 SHA-256: 8877609fb4fe55dcc44ef14285b467faaca3979e6a5acafe0fc80bd4e8b57709
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious. It contains a large number of embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, suggesting a phishing or malware distribution attempt. The ClamAV detection further confirms its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://www.loscam.com/lib_common/ckeditor/ckfinder/userfiles/files/juxojumemipemuli.pdf In PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/6b1938022f0ba85a898a00ac7a79994a/bizemo.pdfIn PDF document text
    • http://suchanekstomatolog.pl/files/file/55952154873.pdfIn PDF document text
    • https://afayl.com/userfiles/file/ketubunepawovenaxadaxom.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/78712f568b743b4f803f6363d1a8772b/53454619526.pdfIn PDF document text
    • http://myblindz.com/fck_user_files/file/kogitokol.pdfIn PDF document text
    • http://pcwenhua.com/uploadimg/file/16247589762042847200.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/86a124ee9efe89debb872f5e5b2930cf/busegujuwidumifebada.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cff7559c24d---pavosejevibowaragu.pdfIn PDF document text
    • https://totspotdaynursery.co.uk/ckfinder/userfiles/files/xonuwi.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b00370fad1---ronekipilemuxedotusujew.pdfIn PDF document text
    • http://neurooperations.com/ckfinder/userfiles/files/32808201485.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/d1c41f3f793b3fbf97d10e1ff1b4fbe0/xulamixulas.pdfIn PDF document text
    • https://nepalipublisher.com/ckfinder/userfiles/files/dotamiweruwizasikumoxa.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/k03th7mdr14kbdad5keah4a646/77720848844.pdfIn PDF document text
    • http://hijoin.hu/editor_up/46338441788.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a41e397cfdc---jowavefumekotasulal.pdfIn PDF document text
    • https://qualityroofinnandsuites.com/nbloom/fckuploads/file/76001700653.pdfIn PDF document text
    • http://huarui-bio.com/upload/files/82104906398.pdfIn PDF document text
    • http://fujieshubao.com/zk/UploadFile/file/2021081702220773499.pdfIn PDF document text
    • http://labsshop.com/d/files/pofuduxodojama.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/94dc542f0e28c13330b6ef665e2ccd54/87629278903.pdfIn PDF document text
    • https://rh-h1tapi-turbo.com/contents//files/21665089176.pdfIn PDF document text
    • https://ehbo-oostkapelle.nl/userfiles/file/ninaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=water+dog+book+pdfPDF 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_off0000d40f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD40F 10488 bytes
SHA-256: d115631cc08b1864107db7bfe788181747da6eff55ab13d931a530de03a57f54
font_01_sfnt_off0000eba8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103BA 18452 bytes
SHA-256: d51c9c55e80bb0703cda661137c93c02becb220b011a83e0c112736189e4111e