Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa66e5c3b3095fc5…

MALICIOUS

PDF

85.5 KB Created: 2021-09-06 15:35:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 68273bca45616e1b11ad4ff936d2b32a SHA-1: ac4ea5427fa7a053faff0b7213896b8e61ffa1e8 SHA-256: aa66e5c3b3095fc5e30fc0654228fbd23cc664b53c73f9c0a828f846af750953
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 URLs, several of which are hosted on compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose.

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 https://novahealthclinic.ca/userfiles/file/87672135578.pdf In PDF document text
    • http://drapikowski.pl/uploaded/fck_files/file/kafosilidilozovo.pdfIn PDF document text
    • http://iworking.vn/uploads/files/39938949995.pdfIn PDF document text
    • http://belniig.by/public/file/wizenideremum.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb61d54285---jefamawiguxekevato.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a184a324d1e---94779583173.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/3238eee0ca0bdfa486150b73ae46b5d8/tonaxaxagudosigimezarowa.pdfIn PDF document text
    • http://www.alquilerbares.com.ar/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8d928b624---koguduta.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/0f872bd245fb4c11b8979b17d64f54de/dumalenaxawuxufe.pdfIn PDF document text
    • https://tessuno.com/upload/files/612af8052a0d0.pdfIn PDF document text
    • http://saydersan.com/firma/files/56791266927.pdfIn PDF document text
    • http://novelinternationalschool.com/ckfinder/userfiles/files/luxizoti.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a635a34e23e---wadojifukaxila.pdfIn PDF document text
    • http://bellamy.tw/uploads/files/202109052006045101.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/32879623075.pdfIn PDF document text
    • http://chinazzjx.com/d/files/2839310180.pdfIn PDF document text
    • https://et-auditing.com/userfiles/files/mopogugekevuwixasulisuzo.pdfIn PDF document text
    • http://chromoink.com/updates/file/59605057929.pdfIn PDF document text
    • http://carrollcountylawyers.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lokodikoxavexugogemedagem.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a5d4c266bfe---39915798935.pdfIn PDF document text
    • https://www.apollopowersystems.com/wp-content/plugins/super-forms/uploads/php/files/6034780095181ae20b5a508a87956737/lipepewumojof.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160c6a9a4586d5---xemedurigakakexikufosote.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a4fd24eaf6---5823239691.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=toyota+fortuner+2017+user+manual+pdfPDF 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_off0000e778.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE778 11088 bytes
SHA-256: 3a128ff66cf777cac2b0b14957525661123d8380ef4d55f7ea01f9ddde332056
font_01_sfnt_off0001017d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1017D 17888 bytes
SHA-256: 79a2944963626e84c5dc24e6b92818c185a79244b2bb252080ac74605dac943a
font_02_sfnt_off00013012.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13012 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1