Malicious PDF — malware analysis report

Static analysis result for SHA-256 8803aa95c028792b…

MALICIOUS

PDF

85.1 KB Created: 2021-08-09 21:57:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 965f1fc9b6439aebccdb221f135a50f6 SHA-1: 3f54157f6da21963bf01b3ccf9cf6139928a60e3 SHA-256: 8803aa95c028792b1453d32e7fb8171a716fd8fc2c054b3a5b1253c3a23ecbeb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious Link

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised WordPress uploads and disposable hosting sites, likely for phishing or malware distribution. The presence of numerous external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://nomylo.ru/uplcv?utm_term=how+to+save+whatsapp+media+to+sd+card PDF link annotation
    • http://stevis.cz/files/file/xitagusopodi.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160d1aca9a6da3---totebijovojakowomexe.pdfIn PDF document text
    • http://daiichihr.com/uploads/news_file/jefanuvanunirozis.pdfIn PDF document text
    • http://hy-concrete.ru/d/files/xiwewelekumovavix.pdfIn PDF document text
    • http://asupuro.com/user_data/image//file/79418511776.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f2a24eb497f---joturaranorijukurewagoluj.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/17sr2tatddsks7ti1kek8m3mb4/pakazuluwap.pdfIn PDF document text
    • https://dildendilecevirievi.com/upload/ckfinder/files/boruma.pdfIn PDF document text
    • https://topplene.com/upload/ckfinder_temp/files/20210611050508.pdfIn PDF document text
    • https://mbzl-pro.xyz/web/img/podborky/files/7400030607.pdfIn PDF document text
    • http://ecole.ru/text/images/file/7481768359.pdfIn PDF document text
    • http://wuxihemei.com/ckfinder/userfiles/files/20210717_170354.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/due30hd1kl3v3h7pcnprm46eag/40720026357.pdfIn PDF document text
    • http://xn--b1adbbbaeqjtsflbfms0e.xn--p1ai/pict/file/kimuwuvaniwibi.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b66ace9d5f6---lojikopuzed.pdfIn PDF document text
    • http://pilanatofishing.com/home/sandbox/domains/shelter.sandbox.tritek.hk/public_html/ckfinder/userfiles/files/ruzodosofuwagamaluguf.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/gifugizazabururujobojonem.pdfIn PDF document text
    • http://gymostrov.org/gymostrov/userfiles/file/newekulur.pdfIn PDF document text
    • http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a79b0aeb988---98743928257.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/63655012446.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc8eb11586---vawewowamuzalumelipa.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/72403d822481c1c0a9e17278ba56f66f/jexemixorunusomowatin.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f16370212ba---62528981174.pdfIn PDF document text
    • 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_off0000e963.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE963 16456 bytes
SHA-256: 5bdc64ade3c17fa06c9bbba80679362375301f298283fc520f8bab46afd4ca5e
font_01_sfnt_off000113f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113F6 10772 bytes
SHA-256: 7155e9877a44502856d27565a864c9fce8fe0522c57140ee19b2380acb28cd83
font_02_sfnt_off00012ccc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CCC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1