Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd88716105fa29f6…

MALICIOUS

PDF

98.2 KB Created: 2021-08-08 07:14:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6beb0608592f2ade6a220a06aa03bf21 SHA-1: 38063260857f62f8a0d58313946dc23674956540 SHA-256: cd88716105fa29f6db7cded76ce49e2eaadb64448d8c1a554ce8228c7ff4af90
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with many URLs pointing to potentially compromised WordPress sites or disposable domains. The PDF structure and numerous external links suggest it's designed to lure users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9876

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://peaceinsrilanka.lk/userfiles/file/sefatuminelozoj.pdf In PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/nikuxuxavetagap.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/85106e08293b54be199f1e23cbdd824e/zufegimomideterow.pdfIn PDF document text
    • http://massvt.sk/editor_uploads/system/files/70708819858.pdfIn PDF document text
    • http://greenvisioninternational.gm/userfiles/file/lokisegibaneju.pdfIn PDF document text
    • http://xiaohecollege.com/d/files/tovuboviverem.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607610b9de718---fagufudatutakaragej.pdfIn PDF document text
    • https://efficimm.fr/userfiles/files/95641344540.pdfIn PDF document text
    • https://allcreaturesinc.com/files/files/64353839280.pdfIn PDF document text
    • https://tonymusic.se/UserFiles/files/40749520381.pdfIn PDF document text
    • http://schubert-hh.de/image/file/9630493862.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bf4cdd8a189---47474923090.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/09f15698749148fbdd637b94b37d1141/48288415556.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/c10714245a798f82491b71be7343dc37/wiwanox.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/ouu2me31ro441op09sh3c05ju4/68348059471.pdfIn PDF document text
    • http://peoplefineart.com/assets/202107/files/20210725125415975688.pdfIn PDF document text
    • https://loctra.net/userfiles/file/98699630634.pdfIn PDF document text
    • https://avflash.nl/upload/files/43389753613.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/h3mlepbgano3vshc2denmvmr82/86032894510.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/4tvorcogj4aqftq1f4mboq5f17/gabuzanibun.pdfIn PDF document text
    • https://juhaszautovill.hu/userfiles/file/solipoxusotopuv.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160f415c187186---78162054822.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/pemabivexonizolux.pdfIn PDF document text
    • http://fobas.cz/userfiles/file/vaselonivegimiroben.pdfIn PDF document text
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/0856aa1e2fe2053e81762306e8c8ba4c/39266050438.pdfIn PDF document text
    • http://akvari-um.ru/userfiles/file/rizunodosasizowaku.pdfIn PDF document text
    • http://hotelgiottotorino.com/userfiles/files/57108204162.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=objetivos+especificos+de+motivacion+laboralPDF 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_off0001171a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1171A 18912 bytes
SHA-256: a097512c3ef2aa95c7d6950bef88f977bc2455367fcfc2e1ce38193e25ac8efa
font_01_sfnt_off0001471a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1471A 11144 bytes
SHA-256: 56a7bccf4d9ded57a62f8317acc40f70384c7cbbc5cbed6d74827010405c4e11
font_02_sfnt_off000160eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x160EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1