Malicious PDF — malware analysis report

Static analysis result for SHA-256 b0b0875c5e181474…

MALICIOUS

PDF

77.9 KB Created: 2021-09-04 16:02:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: cde76c284801901ff11de6608bc63445 SHA-1: 59c073f67c84a8973498bf0392ca40b7c0581d17 SHA-256: b0b0875c5e18147442631690bcd5c01b66045630655b6ae6bb1a0d584411874c
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The presence of multiple external URIs and link farm heuristics supports the conclusion that this document is part of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://philabc.ru/uplcv?utm_term=herbivore+carnivore+omnivore+worksheet+grade+3 PDF link annotation
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/9b10b7ef06c77f70cd0c4b63d054ba61/20285015188.pdfIn PDF document text
    • https://angkortaxiservice.com/userfiles/file/47838150278.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/284dea94433656253d6c62b4d06772b3/39968242160.pdfIn PDF document text
    • http://almar-bus.pl/userfiles/file/gumekupaj.pdfIn PDF document text
    • http://quaint-house.com/images/blog//file/wutaxuk.pdfIn PDF document text
    • https://conexusinternational.com/ckfinder/userfiles/file/xokojix.pdfIn PDF document text
    • http://produccionesproezas.com/clients/2/28/28ea8f13eb032e89cab2838ec144e7af/File/17243566740.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/91015194186.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/kemula.pdfIn PDF document text
    • http://woods-china.cn/ci2/userfiles/files/20210621053536.pdfIn PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/eb89451172c1d562f35684e654dc86e2/54878606010.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/65921838396.pdfIn PDF document text
    • http://talleresjpg.es/img/file/12024972075.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/f86083129dfb2f890e18540742872d4f/22682636826.pdfIn PDF document text
    • http://densayhongngoai.com/uploads/userfiles/file/tipulexumujipipobidi.pdfIn PDF document text
    • http://moveworldtogether.com/datas/files/zupab.pdfIn PDF document text
    • http://kapsalonvogue.nl/files/file/43700560535.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/vumogisaji.pdfIn PDF document text
    • http://autoscuolepintozzi.it/userfiles/files/84972869937.pdfIn PDF document text
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/b0600954b6d3ff224cb793428a8bdc00/82360640283.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_off0000c937.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC937 11316 bytes
SHA-256: b589f5c1fc58aebfcb819586537664e830e6e5fb36a0946d8283685ec264ff09
font_01_sfnt_off0000e381.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE381 17776 bytes
SHA-256: bf9450e3cb8592889fa6442b08ccf2a72c23e5b4bec8d0514f8798fdba936a2e
font_02_sfnt_off0001117d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1117D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1