Malicious PDF — malware analysis report

Static analysis result for SHA-256 10611008a0a46a9c…

MALICIOUS

PDF

83.0 KB Created: 2021-08-21 11:33:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f2b9977a7c5438442d941b5be8784dde SHA-1: f09b52380a9082808e6f90ba4d41e02c261c47d0 SHA-256: 10611008a0a46a9c36ab5132ce94e2fc1c99b178ddb86b8b8ae1e9c9f1ab4dcf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm pointing to compromised WordPress uploads and disposable hosting. The embedded URLs, despite some being marked benign, contribute to the overall malicious intent of directing users to potentially harmful sites. No scripts were extracted, but the PDF structure itself is used to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9902

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://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/5non2vj164547i3q019u98jia3/tijudivon.pdf In PDF document text
    • http://centronegozi.com/public/37887246993.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160b2ad7a9cfc6---tivibuwizulifa.pdfIn PDF document text
    • https://bestofbucerias.com/upload/file/992205157.pdfIn PDF document text
    • http://nuovojob.com/userfiles/files/41966121326.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/160744262a73ef---duzipifepir.pdfIn PDF document text
    • https://micro-churches.net/uploads/file/masidiwavetezazelexod.pdfIn PDF document text
    • http://a-xian-coat.com/uploads//files/202108061214185451.pdfIn PDF document text
    • http://meruzhankhachatryan.com/app/webroot/files/file/laragib.pdfIn PDF document text
    • http://hermangroupcorp.com/clients/3/38/389628ddbd62db2fa1e4299ecdfc1861/File/44836635533.pdfIn PDF document text
    • https://movimientofamiliadejesus.com/images/uploaded/file/gaveluwi.pdfIn PDF document text
    • http://www.donboscovizag.org/images/files/78115334874.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/oj057siqmuf55pb244dtf3m115/vumipujopukofo.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/c6ea94587a3aa17f5d7d247d1d20dfbb/6979843505.pdfIn PDF document text
    • http://esistore.be/userfiles/file/15585406623.pdfIn PDF document text
    • https://www.demetagras.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070baa8ec9bf---98175658048.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/a919aef5ffed012738cec485fc121e1a/32733166984.pdfIn PDF document text
    • http://tachikawa-derma.biz/ckfinder/userfiles/files/22894713762.pdfIn PDF document text
    • https://htchninc.com/d/files/55598602425.pdfIn PDF document text
    • https://hizlipin.com/calisma2/files/uploads/69549688894.pdfIn PDF document text
    • http://sdds.be/userfiles/file/49932011226.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/temaretij.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ee815db66a---jamukofaw.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/dusojoto.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0a294b756c---4999914399.pdfIn PDF document text
    • https://www.alarisusallc.com/wp-content/plugins/super-forms/uploads/php/files/b75f06d797f0f010998dff544ce82a85/zonazu.pdfIn PDF document text
    • http://aylincinarli.com/fckfiles/file/5397248992.pdfIn PDF document text
    • http://gift-founder.com/archive/upload/files/famepefoxiboxipakoze.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=lunch+meeting+invitation+email+templatePDF 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_off0000e064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE064 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f87b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF87B 10676 bytes
SHA-256: 99a065019a6ee50e1beb3a794130a96187894cdf057b1d815e4c49573fd2c2b6
font_02_sfnt_off000110bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110BD 16908 bytes
SHA-256: fad99cfec61401107efbffc50adbfa2f11eefd2e6db893e90f3624f3bbddf99f