Malicious PDF — malware analysis report

Static analysis result for SHA-256 7800e0adfc6b5d91…

MALICIOUS

PDF

86.3 KB Created: 2021-09-19 07:13:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1abe7b8c4ed1d7238f45465c487a55cf SHA-1: adbf5f9bc789f35e92cf332b5fed00a9c34d505b SHA-256: 7800e0adfc6b5d91ba0ba6b14a0583822c63aea0ee073eba0e1223aafeb933c0
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous other PDF files hosted on compromised CMS uploads, indicating a phishing or SEO manipulation scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely involving the exploitation of PDF vulnerabilities to deliver a payload. The presence of multiple external URIs and a link farm heuristic points towards a campaign to distribute malicious content or redirect users to phishing sites.

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 http://confidenzacsapagy.hu/upload/72271991058.pdf In PDF document text
    • https://saikekanglun.com/filespath/files/20210917133322.pdfIn PDF document text
    • http://nachhilfeschule.havonix.com/ckfinder/userfiles/files/1939369027.pdfIn PDF document text
    • http://maximaviajes.com/FCKfiles/file/bepabo.pdfIn PDF document text
    • http://avandcie-energy.fr/ckfinder/userfiles/files/saveboxekedotagasupezuzi.pdfIn PDF document text
    • http://www.recko.ru/ckfinder/userfiles/files/81232971952.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/8d35440b1b2cc4e3c28585dce8904540/85280294596.pdfIn PDF document text
    • https://gogreenonline.net/userfiles/image/fckeditor/file/vezonazofagazagefalasaz.pdfIn PDF document text
    • http://shyjjc.com/v15/Upload/file/2021914648153410.pdfIn PDF document text
    • https://leanuslab.com/UserFiles/file/20827913356.pdfIn PDF document text
    • http://apsencollege.org/test/fckeditor/file/wufebitirujudogex.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16143bc37c184f---35264328410.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161409b4f4bb9a---9536015614.pdfIn PDF document text
    • http://orenprom.com/img/account/file/78597355644.pdfIn PDF document text
    • http://jfac.kr/ckfinder/userfiles/files/58096683718.pdfIn PDF document text
    • https://stepweystudy.com/ckfinder/userfiles/files/nogapumisiduvuvukugone.pdfIn PDF document text
    • http://igabana.com/upfolder/e/files/20210901142654.pdfIn PDF document text
    • https://suacuasathcm.com/uploads/files/58833047488.pdfIn PDF document text
    • http://naphotelbangkok.com/userfiles/files/pelidogabuzulipuk.pdfIn PDF document text
    • http://mosvag.ru/img/lib/file/28449277299.pdfIn PDF document text
    • http://tnslib.tools/userfiles/files/mopojabulitidugigurov.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c813243cf4---babadoj.pdfIn PDF document text
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/gce0h9q0cesihfoq7r5ievkrgs/zolig.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=apps+getting+closed+automatically+androidPDF 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_off0000ea71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA71 18056 bytes
SHA-256: ada32c0273a16ca0d731b209a9981e82524a15fb71c11410a7b23625487f9a89
font_01_sfnt_off0001195d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1195D 11052 bytes
SHA-256: 20bb5dfac95354f5d7e3ccb685cda56a8af77da320844371de70cd92d406b67c
font_02_sfnt_off000132f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1