Malicious PDF — malware analysis report

Static analysis result for SHA-256 cffef01f5048f2de…

MALICIOUS

PDF

73.9 KB Created: 2021-09-03 19:04:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: cd99f7b76331e4528bc19963d06dc390 SHA-1: a909872b48a89631d9dcde52ab219a9ae1bb557c SHA-256: cffef01f5048f2de1a193a8639ebff35d98fec80a03f426e50f2144ea5033699
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. The document functions as a link farm, containing numerous URLs pointing to various websites, some of which are hosted on compromised CMS uploads or disposable domains. This pattern is consistent with phishing or malware distribution campaigns, where users are lured to malicious sites via seemingly legitimate documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://ofcourselc.com/admin/uploadsfile/werasatatuxima.pdf In PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c3aca451a5b---wifakulozi.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a43ca9ec07d---53885981187.pdfIn PDF document text
    • http://vinaktv.com/storage/ckfinder/files/38319788463.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/4adcf5c446596be0a412d308158a1daf/89538127475.pdfIn PDF document text
    • http://myphamasia.net/upload/files/68349952071.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/89546506405.pdfIn PDF document text
    • https://drnanemilk.com/tctt/sites/aaa/file/25054613197.pdfIn PDF document text
    • http://chinazzjx.com/d/files/19317352190.pdfIn PDF document text
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/ded5eb9586b7b4c684c32582fd92e76b/lajemadake.pdfIn PDF document text
    • http://world-housing.jp/ckfinder/userfiles/files/sazinula.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a92cd7d7f88---86942508963.pdfIn PDF document text
    • http://www.kymkarajok.net/tiedostot/files/28808216001.pdfIn PDF document text
    • http://gryfarmerskie.pl/pliki_wyswig/files/82068587839.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/6pf3p6gphui8pv37bbc2ck98k6/19431779323.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/060ab3e53df0452024c962c9f5052a47/87847627348.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/c498273c42b816f42d12947c706889a4/felezawegawimikikode.pdfIn PDF document text
    • http://amdind.com/userfiles/file/53143612249.pdfIn PDF document text
    • http://chiengthai.com/file_media/file_image/file/56671343073.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/7683269038.pdfIn PDF document text
    • http://livestocktool.com/d/files/wizurosesijevu.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/16105382ee2100---gudimemesoren.pdfIn PDF document text
    • http://xn--80aafjbaeihgganggf9ajkncugh2a.xn--p1ai/pict/file/43456791826.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=sociology+cape+syllabus+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_off0000bc75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC75 10920 bytes
SHA-256: 7a7937c899f3f453ef5ebb163903990c85575c74769f310b6e96c770a88fd044
font_01_sfnt_off0000d56b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD56B 17484 bytes
SHA-256: 6b1087f7b3b0358ceffbd5164eff0da826163c346c00ca3abc220ca5a5177eb7
font_02_sfnt_off000101c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1