Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8c0f2fc89821252…

MALICIOUS

PDF

83.4 KB Created: 2021-10-05 16:19:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 02f3cc6604c2ea2bba3d6126489b2471 SHA-1: 2102883d32a307bc47029413a6e5c98bd1b3ee89 SHA-256: a8c0f2fc89821252cc09b01922a3ba65e3e28763fb8fb264a31a8471e1acbce9
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The embedded URLs suggest an attempt to distribute phishing content or further malware payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://darslaska.org/ckfinder/userfiles/files/doxikosunererinu.pdf In PDF document text
    • https://gtpoznan.pl/cms/files/file/pajojavozuzufejaduserur.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/xekonanomif.pdfIn PDF document text
    • http://telesson.net/_UploadFile/Images/file/tinef.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/161344ba5a7236---76405983939.pdfIn PDF document text
    • http://firsttimehomebuyerstudy.com/images/file/semudi.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/161461d4a788e8---nibopupevetalejonivasuzew.pdfIn PDF document text
    • http://navrattan.co/userfiles/file/nudafasodabufivaburin.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/3736edbdc517c5573138b956a2582b3b/vumebazono.pdfIn PDF document text
    • https://bozoklar.org/ckfinder/userfiles/files/79199164681.pdfIn PDF document text
    • http://www.hkimm.hk/_bin/ckfinder/userfiles/files/segob.pdfIn PDF document text
    • http://hgbs.de/userfiles/file/tarewosiwamumigemoraxele.pdfIn PDF document text
    • https://losungversorger.com/product/file/zedifana.pdfIn PDF document text
    • http://opuspoint.com/ckfinder/userfiles/files/sakalenigil.pdfIn PDF document text
    • https://mystruggle.uk/indigo/ckfinder/userfiles/files/11185157321.pdfIn PDF document text
    • https://manhremhoangvan.vn/wp-content/uploads/files/1637832043.pdfIn PDF document text
    • http://thephinhmienbac.com/upload/files/lifewunu.pdfIn PDF document text
    • https://vantainoidia.vn/ci/userfiles/files/56715504692.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/686905152bd3a52091de7f830c2af95f/xuravipamulukageziv.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/4moo37j58nut0uf6l9644ev50e/wimufufufop.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/6931033319b15a8d03b0f1c30a25a036/14692425004.pdfIn PDF document text
    • http://jmk.kr/ckfinder/userfiles/files/rovowaveselu.pdfIn PDF document text
    • https://maytinhdalat.vn/images/uploads/files/87289027380.pdfIn PDF document text
    • http://lawfirm.vn/MINH/user_files/file/togutezurutoreguze.pdfIn PDF document text
    • https://www.piramideidiomas.com/ckfinder/userfiles/files/xitevodogom.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=past+perfect+and+perfect+continuous+tensePDF 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_off0000db4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB4F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f366.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF366 10668 bytes
SHA-256: a1fe41e659a5fd76da2419cf0ebdad7a1e8005453a4a71ff5dc5a1285cbb37ee
font_02_sfnt_off00010c00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C00 19980 bytes
SHA-256: b7bfe6d2e2f08d8b0dd2984ea52954ddd08e4259bcac4722043e3a985d2698e0