Malicious PDF — malware analysis report

Static analysis result for SHA-256 90988a38e9507123…

MALICIOUS

PDF

86.7 KB Created: 2021-09-01 08:28:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1ec281b390fa8ed63d913e2db3b1a359 SHA-1: 6ba9b0101d55df6f5e7ffe8b4a1edb9da29ce99d SHA-256: 90988a38e9507123f75bb6218237dc72fccfd379ecc6146fc0e99807b409316e
156 Risk Score

Malware Insights

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

The PDF file contains a link farm directing users to multiple external websites, with a significant number of these links pointing to compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL analysis point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://alrukn.co/userfiles/files/bilinemebarizatizovel.pdf In PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610336efaf79c---xilelujikerap.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b9e5cfae676---7132657588.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b83c0804b3---tesuditukopugove.pdfIn PDF document text
    • http://casaatlantida.com/userfiles/file///zopujuzisovifusodav.pdfIn PDF document text
    • http://d4svancouver.com/clients/c/c8/c8601140a4283eb9b700f388a83987a3/File/8342893066.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/41804244069.pdfIn PDF document text
    • http://jvcc.cn/ckfinder/userfiles/files/2108070517300480767lg2g.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/80fdc663f53bac18ba3c9c30a6a4f8ab/woponovuziketonifomokusa.pdfIn PDF document text
    • https://vetregistr.com/ckfinder/userfiles/files/86917615978.pdfIn PDF document text
    • http://eastcity.hu/ufiles/file/nobijefazofavuladabame.pdfIn PDF document text
    • http://starcity-vinhomes.vn/app/webroot/img/files/87088349347.pdfIn PDF document text
    • https://flyags.com/editorResources/file///91597829624.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/alrm7kq8tdf5n0fu9mlap7t530/4031532541.pdfIn PDF document text
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/65807798360.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/po8mo5gmrq4dfoquvrd81k0h02/81961631130.pdfIn PDF document text
    • http://casier-a-bouteilles.com/file/29263003595.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608212bd93ffd---1452133634.pdfIn PDF document text
    • http://tele-video.ru/upload/files/26383073093.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7336248b2---61665655645.pdfIn PDF document text
    • https://betenrealestate.com/sites/default/files/file/20996324634.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b5ecdc98ffb---jotisurizuzazej.pdfIn PDF document text
    • https://maggies-handmade.com/UserFiles/files/tejadebojanozaloj.pdfIn PDF document text
    • https://airtelco.com/data/users/_/email/files/80927631857.pdfIn PDF document text
    • https://blokhol.com/upload/files/37092104235.pdfIn PDF document text
    • https://asset-books.com/userfiles/file/31808334914.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=what+is+the+purpose+of+a+research+questionPDF 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_off0000ec9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC9E 10768 bytes
SHA-256: f00b3e5de797715f517f7ed37d9f06d6c98bc578978f89ea28bb451056f89cc7
font_01_sfnt_off00010564.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10564 17988 bytes
SHA-256: a0644521acdc8a789410d6d304a479ef644720f66ad7bd388bbc48ca23c7b123
font_02_sfnt_off00013424.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13424 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1