Malicious PDF — malware analysis report

Static analysis result for SHA-256 72a87b391bbe8885…

MALICIOUS

PDF

88.9 KB Created: 2021-09-01 01:08:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 33a0892f53aa4d41ed035ba9bc44f58a SHA-1: 04eb94dc33f5c31b0f2bf5db20ea246f0225a182 SHA-256: 72a87b391bbe88855f0490d3037a63ec0208525f39325fd594bf3a175711f755
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, pointing to numerous compromised WordPress upload directories and disposable hosting sites. While no scripts were directly extracted, the nature of the link farm suggests it is likely used for phishing or distributing further malware, aligning with T1566.001 (Spearphishing Attachment) as a potential initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://drivescuolaguida.it/userfiles/files/42898610009.pdf In PDF document text
    • https://100tmt.com/uploadimage/files/20210821094621.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/7g7avhb09hgivd6v6i6kds6i3s/legofevujuwafizaxo.pdfIn PDF document text
    • http://aajude.pt/backoffice/ckfinder/userfiles/files/bonaxavawigolalatalit.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/160b6aa554fab3---34243667606.pdfIn PDF document text
    • http://geyikkimya.com/userfiles/upload/file/99296434266.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/5f6395c292e8b6e62858b82deea0381a/32062601650.pdfIn PDF document text
    • https://htchninc.com/d/files/82012012068.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad9d59e4be2---gibefelonejotunomumetodut.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f34994c5a2---20192192737.pdfIn PDF document text
    • https://seerupit.dk/assens/file/40010557548.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/75420947.pdfIn PDF document text
    • http://pamatudarbai.lt/ckfinder/userfiles/files/56308356457.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607d11e27a74f---54879230513.pdfIn PDF document text
    • http://jualumnitoronto.com/editor/uploadfiles/boditogopelakazosob.pdfIn PDF document text
    • https://acornschoolcharleston.org/wp-content/plugins/super-forms/uploads/php/files/b3857b70e92b18e4917f2abf3ac695c2/47025351795.pdfIn PDF document text
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/45897624954.pdfIn PDF document text
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/ccfa1d7113302080eab9ebda2e4c1fc0/dotomodemubeziwexovaji.pdfIn PDF document text
    • https://hagabb.ro/ckfinder/userfiles/files/31256854553.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1611de98e909f8---11657802655.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/t41hofrcn0cgv0mqs0cs6161j0/zonoraripaxukitidid.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/95707058190.pdfIn PDF document text
    • http://nirmalapublicschoolerumely.com/userfiles/file/wepivinoxufatugazef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=rudy+and+erisPDF 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_off0000f41f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF41F 10236 bytes
SHA-256: 1396fb46eecfedf1757a149f91e9f27f61447e280a564e5a21b25b610f351165
font_01_sfnt_off00010b36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012348.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12348 19036 bytes
SHA-256: 6dc8d10819150472ffeac3e22bf337d15d4b644990aba81a1c66aa0f0345a970