Malicious PDF — malware analysis report

Static analysis result for SHA-256 c77618de3f7d0cb0…

MALICIOUS

PDF

86.3 KB Created: 2021-07-03 12:19:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: c939fd66a2c99efa4da25d7d5a165668 SHA-1: 49a341dda153cba72ed7f2a96c255110307623a1 SHA-256: c77618de3f7d0cb034a3f7f2180cb484c688cf40ab2511f461d909c1a8d7eded
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The document contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting it functions as a link farm. The presence of these links and the overall structure indicate an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/11af55c83960260170860b68a163dc2d/63859576925.pdf In PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d3678d0dfc0---36822549572.pdfIn PDF document text
    • http://24cvety.ru/upload/files/subuwaveviza.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086ca8962a4c---gejufaka.pdfIn PDF document text
    • http://bebelino.ru/userfiles/file/97692115647.pdfIn PDF document text
    • http://hutergroup.de/userfiles/file/39202516511.pdfIn PDF document text
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/bbd6e0f509efd65cca374879564edbe4/zegaguvezep.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160723d4d73d24---kevololarijivopugugedi.pdfIn PDF document text
    • http://auapp.ch/userfiles/files/nekeliwutugegajozezorune.pdfIn PDF document text
    • http://graylegalservices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/39930581224.pdfIn PDF document text
    • http://www.specemc.ru/upload/files/ledolaxipowijedezatatara.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-5-23/20210523023953733864.pdfIn PDF document text
    • http://yjsyrj.com/userfiles/file/88527264070.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/8ef61b3dbee045f1df267530d5a98eaf/97028305663.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/60f4fd6c01371a18d737e5faba590f5d/74439838472.pdfIn PDF document text
    • http://maychamsocda.vn/images/userfiles/file/migafovutagevemanoz.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c63308eda32---guzetasaxetuvomaxamari.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/11t9tssjtsk7f4jr9qpps5ukl7/vuvilajuwafejes.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e4992dd126---kavokovevazidesewunujipoj.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609aba3f5d1e8---bemumizizutaledoru.pdfIn PDF document text
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087e94894298---20590494955.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/xuxuxojinejixefil.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608b7744beac4---gizarutafoxabovabifujidoj.pdfIn PDF document text
    • http://domusanna.it/userfiles/files/87192078345.pdfIn PDF document text
    • https://led7.ru/file/49556154272.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd921cc8e1---80682705300.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba668b384af---22684794777.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=instagram+followers+free+without+verificationPDF 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_off0000ee6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6C 16808 bytes
SHA-256: 0b3cfa978e7912f5b97287b0307ae8047b6f2a49144baa9a9e1fcaa1266140f1
font_01_sfnt_off00011a08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A08 10988 bytes
SHA-256: 63d040d7e92e2c2a704c956e561dc0f3aa75c5d5340fb78c4c0b934587cf9d79
font_02_sfnt_off0001336a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1336A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1