Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fc437fef62142cc…

MALICIOUS

PDF

111.0 KB Created: 2021-10-19 15:15:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: b8b343c2b1600a67c31af7b335591e1d SHA-1: 350e6a89c34aa2776d492e3db58804eb45f76d50 SHA-256: 8fc437fef62142cc9ffc7bb4ddddb1fe72e3d5a4417e29ef6d51766cc49a2544
126 Risk Score

Malware Insights

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

The PDF file contains a large number of links, many of which point to compromised WordPress sites acting as link farms. ClamAV detected this file as a phishing trojan, indicating a malicious intent to lure users to potentially harmful content. The presence of multiple links on disposable or compromised hosting suggests an attempt to distribute malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier clean score 0.2498

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148019b79089---vamotopovamuj.pdf In PDF document text
    • http://broadgatecapital.com/userfiles/file/walojazidozotinedupoxaj.pdfIn PDF document text
    • http://www.childofafrica.org/media/userfiles/file/80214523414.pdfIn PDF document text
    • http://www.aragonemprendedor.com/userfiles/files/10730241202.pdfIn PDF document text
    • http://smartwealthhk.com/userfiles/noduwax.pdfIn PDF document text
    • http://ohdiabo.net/images/ckeditor/files/61907685096.pdfIn PDF document text
    • https://nasikampung.info/contents/files/33643553830.pdfIn PDF document text
    • https://anaksemut.com/contents/files/28472669228.pdfIn PDF document text
    • https://chulintemple.org/CKEdit/upload/files/54853400147.pdfIn PDF document text
    • http://xn--80aafbkbafwdti1ahihccrg.xn--p1ai/pict/file/lelazujapipitupexozato.pdfIn PDF document text
    • https://currenwatch.myhost360.cn/file/upload/files/09-15-13-37-49-38.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16158a3fd7710a---9464220694.pdfIn PDF document text
    • http://hotelbasantresidency.com/uploads/63030614391.pdfIn PDF document text
    • https://baobiachau.com/luutru/files/26289127230.pdfIn PDF document text
    • http://thesecurityguardunion.ca/userfiles/files/guwasedevoki.pdfIn PDF document text
    • http://3m18.com/images/editor/files/sinasaduxijunabime.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/dcfcfeb61f6db029447bea1260661a91/luzaxagarotutemosojadoxom.pdfIn PDF document text
    • https://aykutemlak.com/upload/ckfinder/files/defenonepeduxilem.pdfIn PDF document text
    • http://uni-farm.pl/ckfinder/userfiles/files/1377933527.pdfIn PDF document text
    • https://hideab.se/tc/Mediagalleri/file/8010727311.pdfIn PDF document text
    • http://kanalizace-ul.cz/userfiles/file/bodotiradutilogedote.pdfIn PDF document text
    • https://camping-du-lac-dijon.com/userfiles/fichiers/90625920371.pdfIn PDF document text
    • https://norservis.info/files/files/70805525549.pdfIn PDF document text
    • https://salvamontbihor.ro/app/webroot/files/userfiles/files/11424111688.pdfIn PDF document text
    • http://avandcie-automation.com/ckfinder/userfiles/files/nezovaregijanozowitat.pdfIn PDF document text
    • https://nichecnk.leaddeehub.com/userfiles/files/59020147687.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/HKUGBsJGI0E/uplcv?utm_term=which+is+not+an+example+of+convection+currentPDF link annotation
    • 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_off00014ed8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14ED8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000166ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x166EF 11008 bytes
SHA-256: e852533e0a665cf28bdf79f35eaa0c9c9d33c428ad581d686c22b0a94e3c26e2
font_02_sfnt_off0001805e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1805E 21112 bytes
SHA-256: 94236c84323af75f6be6a43059a34be4b7ecf809dfb92b57f556bb6c248b7e0c