Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3a51874369fe041…

MALICIOUS

PDF

82.6 KB Created: 2021-09-19 04:14:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c08ca89779d1ab4dbfee7277cc7ee787 SHA-1: cf18cc4c703f4c456f775e6dba295b16e119e3ad SHA-256: a3a51874369fe0418335491a3b1634aa95c244dc2e9b364b50259286332b8099
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 CMS upload directories or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://pixomot.ru/uplcv?utm_term=how+to+delete+duplicate+apps+on+android PDF link annotation
    • https://takipcisec.com/calisma2/files/uploads/mezowetoxijotenega.pdfIn PDF document text
    • https://asiarsolutions.com/userfiles/file/44920891993.pdfIn PDF document text
    • http://topp.pl/_topp/file/84751815670.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/7a5182fc1e13ea9abe0d1ee9705ce087/61272122231.pdfIn PDF document text
    • http://chothuexeninhbinh.net/data/dulieu/files/gikosafedafumi.pdfIn PDF document text
    • https://freebcard.com/ckfinder/userfiles/files/giwidalofe.pdfIn PDF document text
    • http://asude.istanbul/ck_images/files/nadipopa.pdfIn PDF document text
    • https://loyalangkorapartment.com/userfiles/file/wozotutisinevasugi.pdfIn PDF document text
    • http://shoreluxurylimos.com/userfiles/files/45076509479.pdfIn PDF document text
    • http://motivationandmomentum.net/ci/userfiles/files/44485143223.pdfIn PDF document text
    • http://desiaussies.com/ckeditor/uploads/files/xivovemo.pdfIn PDF document text
    • https://traveletrust.com/basefile/traveletrustcom/files/28215520245.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ee00108504---pepisugobidovorepebiweru.pdfIn PDF document text
    • https://kaplaitalia.it/userfiles/files/69927468395.pdfIn PDF document text
    • http://simp-q.ru/userfiles/file/71512879510.pdfIn PDF document text
    • http://www.swaving-stalinrichting.nl/ckfinder/userfiles/files/8975498441.pdfIn PDF document text
    • https://photopoligrafic.ru/ckfinder/userfiles/files/gibogilozifajum.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/fae88b43f1c77a0dd702d0364d49d4d3/36212663224.pdfIn PDF document text
    • https://designclarf.it/file/95672739950.pdfIn PDF document text
    • https://postelezmasivu-liberec.cz/ckfinder/userfiles/files/lupemokufosaxena.pdfIn PDF document text
    • http://ljjxmining.com/uploadfile/file///2021090915093177.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/lugisuratidazeboj.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_off0000dd32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD32 18052 bytes
SHA-256: a263475dfe2600280c5d4ec66f1061b174d691894f609061a16b1b8ef675daef
font_01_sfnt_off00010bce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BCE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000123e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123E5 10684 bytes
SHA-256: 271717e4b9c74df0a643517532cad1e01994eaa35746975dda7410ea9555ee02