Malicious PDF — malware analysis report

Static analysis result for SHA-256 e544b94de5101a5b…

MALICIOUS

PDF

85.0 KB Created: 2021-09-05 10:35:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3c22c165550e5e93c28c7d653019aa52 SHA-1: 868fe9d14d5c32145ee6d7ae60a9e0c1f6a22b7d SHA-256: e544b94de5101a5be8c14f5ca221f4364f53af6654c314dd353fdf46bdc4cb68
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing a link farm pointing to multiple compromised WordPress sites, indicating an attempt to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirm the link farm tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/e23779f435c3729243ee519d96cc77dc/95127373018.pdf In PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160c53a47d4b76---vujanunigebafelixupejuzot.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/ceec7670f6790d0802897a501ef99e81/vojuvixoxovakapulu.pdfIn PDF document text
    • https://ofcourselc.com/admin/uploadsfile/nuwabaxopuwarofijigivepat.pdfIn PDF document text
    • http://salamino.pl/userfiles/file/99604851987.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/160721c4184dca---gofejuza.pdfIn PDF document text
    • http://kredoteka.ru/uploads/file/5990184090.pdfIn PDF document text
    • https://dichvuhappyhouse.com/upload/files/89635075368.pdfIn PDF document text
    • http://szjglaw.com/uploadfile/file/2021083105091273499.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c942743e6b6---savijililunometuvug.pdfIn PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/sabiwaguti.pdfIn PDF document text
    • https://soudurelausiere.ca/upload/editor/file/fininelitofolujixarajate.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/892a6917e1212a5127cb4674c088b46b/kanekanikodipabovedobi.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/92a782d92508f5c1118151904d85ca67/78708206464.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc8c789675d---naziludawizilakugod.pdfIn PDF document text
    • http://backkwang.com/userData/board/file/lejimodebamu.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2f35b28a1b---66441932619.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/gasisosiporenetitos.pdfIn PDF document text
    • http://fli.edu.mn/ckfinder/userfiles/files/faruwuxamofipabufuzeviro.pdfIn PDF document text
    • https://khotelmarket.com/FileData/ckfinder/files/20210603_7344123FAA98EFA2.pdfIn PDF document text
    • http://directartdeal.com/uploaded_files/userfiles/files/rosuf.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/behr610gt8t97juak2lm6q0qci/41586934394.pdfIn PDF document text
    • http://es-hanasaki.com/yamituki-n/uploads/files/sazagu.pdfIn PDF document text
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/v9g657n9n1uvruc06cpdd9o7oj/nedumoguvimidisejakagu.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/pi3l9lss6rjsrmob85dp07fv9q/34322526640.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=handbook+of+nonprescription+drugs+18th+edition+pdf+freePDF 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_off0000e3b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fbc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBC7 11436 bytes
SHA-256: cf4c9e609a2ca7624fab39fb3e8840bad4dfea01b2fac1dc01508aa0990f562b
font_02_sfnt_off0001164f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1164F 18040 bytes
SHA-256: b1021100d66129c3528fdc2882dfd61488750ba80d194da46f2089220cfae6be