Malicious PDF — malware analysis report

Static analysis result for SHA-256 81b40474f4d84eda…

MALICIOUS

PDF

86.6 KB Created: 2021-07-08 08:10:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6237d92d16e5df393626df1da77a7a1c SHA-1: ddc55adbcb0d1a42d4905e92168ce77cb967c96b SHA-256: 81b40474f4d84edaedda13414a86e19279ee0616244c9fcccad6cd2380815e14
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress sites and potentially malicious domains. The presence of embedded URLs and the nature of the link farm suggest an attempt to redirect users to phishing sites or download further malicious content.

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://coretry.ru/uplcv?utm_term=software+wbs+example
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/801fc7e9b56c67e532c1e45793d770c9/wipakufisozeboleluvasa.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/684d418d23dfc0a2b77dde988efc4bfb/23003942516.pdf
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/gdu414tqbamqhhpt1pt0pr3mm3/26459533917.pdf
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/6d45c2a54b03e18412a95d99c2b3451e/xewudodaxepuresumofibenu.pdf
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b0591c66403---tisozifogarebowomux.pdf
    • http://www.aadhar-interior.com/userfiles/file/31663127602.pdf
    • https://www.hotelamoha.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad3008030c---wanelopilifesewujano.pdf
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160e0eeee57536---14510820995.pdf
    • http://hzdsbg.com/uploadfile/1621228052.pdf
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/4eafa32e1f45cfe836316dc75fa92a31/65949716702.pdf
    • http://nowyhotelik.pl/userfiles/file/74234479707.pdf
    • https://liantoong.com/archive/upload/files/78914551192.pdf
    • http://saamfactory.com/wp-content/plugins/super-forms/uploads/php/files/9d1d75dd369ed72c13f205ce62212538/54408338732.pdf
    • http://ackerviewguesthouse.com/userfiles/file/jobetajetafive.pdf
    • http://nappsa.org/userfiles/file/gulajit.pdf
    • http://mulroyenvironmental.ie/userfiles/file/57923380413.pdf
    • http://blessedfamilycovenant.org/clients/c/cb/cb727bc273eb4203dc66fb73741ae5ae/File/rekak.pdf
    • http://osteriadelcampanile.com/userfiles/files/85206678829.pdf
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/d0ed7bf1f770acde2c4297f1f74e8f0f/ronot.pdf
    • http://sola-brothers.com/userfiles/file/47822946172.pdf
    • https://jdrum-music.com/uploads/ckfiles/files/bepomomerutelinapufux.pdf
    • http://eltdb.com/UserFiles/files/98555155655.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f088.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF088 16792 bytes
font_01_sfnt_off0001089a.bin
234684a2fde0401ac0188fe01c3e3fef7f0b61016899cef359f6b33899cb96de
pdf-font-stream PDF embedded font (sfnt) at offset 0x1089A 17040 bytes
font_02_sfnt_off00013508.bin
40d840b5999c60b7291f8d70480f44d4e6a6dbe7e13e05abd4528c1b74999eb1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13508 10728 bytes