Malicious PDF — malware analysis report

Static analysis result for SHA-256 905f9af088f3170b…

MALICIOUS

PDF

96.6 KB Created: 2021-09-19 17:01:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d498a5aef2e4bc2a6d42b31073e33e90 SHA-1: 47b2cd08646f1c27577691f3951664c7505fa5e1 SHA-256: 905f9af088f3170b63f05ab0edaa5508e9978ba8e96a86688fa68a022686c421
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains multiple links pointing to compromised WordPress sites, identified by heuristics as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161396c477094a---lonomazimuxefugif.pdf In PDF document text
    • https://holcom-wd.holcom.vn/webroot/img/files/xubedatubikumadugewugiwip.pdfIn PDF document text
    • https://hamasataccessories.com/userfiles/files/51073741051.pdfIn PDF document text
    • https://panelshock.com/userfiles/file/melajosopurusibi.pdfIn PDF document text
    • http://cpbnatation.fr/fckeditor/userfiles/file/zamilofidogufe.pdfIn PDF document text
    • http://opuspointpartners.com/ckfinder/userfiles/files/guredeg.pdfIn PDF document text
    • http://netdepphunu.vn/images/userfiles/file/55592947298.pdfIn PDF document text
    • http://iktoktatas.hu/files/file/kukazobutepatesadan.pdfIn PDF document text
    • https://vinocastillo.hu/editor_up/gekizijija.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/files/tanajozus.pdfIn PDF document text
    • http://portaldeaquidauana.com.br/ckfinder/userfiles/files/2937606834.pdfIn PDF document text
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/xijodizabagafusoz.pdfIn PDF document text
    • http://mevlanaasm.com/resimler/files/galulum.pdfIn PDF document text
    • http://myphamlulanjina.com/upload/files/xilapikefazijekipoges.pdfIn PDF document text
    • https://laps.pl/userfiles/file/55786989895.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137ba997b93f---kegelefobozez.pdfIn PDF document text
    • http://hwangtosidae.com/userData/ebizro_board/file/timojusodegoditekazi.pdfIn PDF document text
    • http://inoxbienhoa.com/upload/files/wumawenoketixojero.pdfIn PDF document text
    • http://xn--oy2b19v1mb1yi.com/userfiles/file/54726928865.pdfIn PDF document text
    • https://congthuonghotel.vn/app/webroot/files/images/pages/files/fanivofanav.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/25098351240.pdfIn PDF document text
    • https://2ruoteexpo.it/ckfinder/userfiles/files/61625162273.pdfIn PDF document text
    • http://clairvoyantinfotech.com/demo/images/86615520206.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1613d2e9947443---lumisulewivomimarafevowil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=sangandaan+caloocan+city+zip+codePDF 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_off00011674.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11674 17800 bytes
SHA-256: 229bd90f42b5e25a0abe8a882cedc63638b6ba5deb6eb03a96ab9816b4ec6293
font_01_sfnt_off0001449a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1449A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015cb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15CB1 10672 bytes
SHA-256: 7f4ca6eab5eef21d91775b43074d2e8c5f92a82a18bded13bd9a2c8fcc10f5dc