Malicious PDF — malware analysis report

Static analysis result for SHA-256 a52126adbcda086a…

MALICIOUS

PDF

82.0 KB Created: 2021-09-05 04:21:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 98643cf37964fb08e489c8ad526ad69f SHA-1: 7a5f76edf049c3538c3ebf037c9fd15ffbc33479 SHA-256: a52126adbcda086a11450799832a2711e0ad7be8b96f568fb789969e13fffd9e
164 Risk Score

Malware Insights

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

The sample contains embedded JavaScript, which is a common technique for executing malicious code within PDF documents. It also features a link farm pointing to compromised WordPress uploads, suggesting an attempt to host and distribute malicious content. The ClamAV detection and ML classifier further indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/692ee8845e0b767a83f491dda3c9b746/27698388014.pdf
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16098304edcd2f---94741063010.pdf
    • https://searchlink.org/userfiles//file/60124091964.pdf
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0dc66a46e---pozejelosukotuveneti.pdf
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/16084d2c8dc241---bufoduvasogetoxatekisoxe.pdf
    • http://hanasushichoice.com/uploads/files/terubef.pdf
    • http://cmuniontravel.com/userfiles/files/79105247592.pdf
    • https://angkorphotographyguide.com/userfiles/file/silimaviluvufutokebura.pdf
    • http://leinerpakgelatine.com/survey/userfiles/files/tajulatakezimumatulipabaf.pdf
    • https://barcelonacentremedic.cat/files/galeria/files/18813461906.pdf
    • https://pezenasenchantee.fr/userfiles/file/kudemiwuliru.pdf
    • http://karimeh.com/public/userfiles/file/69051252056.pdf
    • http://turskazka.ru/ckfinder/userfiles/files/21968715222.pdf
    • http://ty-universe.com/image/files/20210708_115319.pdf
    • https://paeonia.ch/userfiles/files/litifedidenexotojafazaro.pdf
    • https://artbynela.com/uploads/file/dafipunejenepexodavoze.pdf
    • http://reicar.dk/userfiles/file/4072587500.pdf
    • https://muguet.fr/sites/default/files/file/dodazelezifav.pdf
    • http://carnow.jp/js/upload/files/27388558562.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/82e35100f60a3f53c8a757caf92f8a7f/26456139369.pdf
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0b44fd855c---rager.pdf
    • http://sanmargholidays.com/ckfinder/userfiles/files/75383349255.pdf
    • https://suruburi.net/mm/file/95911589804.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=commutative+property+of+addition+2nd+grade+worksheets
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d93e.bin
43964dbf492e21e70db23cf4ced10b9c9112b0893a29e27ad010e2f65eb5210a
pdf-font-stream PDF embedded font (sfnt) at offset 0xD93E 11508 bytes
font_01_sfnt_off0000f440.bin
5d896595f668aeab4249d1464e0777c7ce7f9665e324eddd0ed6df950f44de5a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF440 17964 bytes
font_02_sfnt_off00012263.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12263 16792 bytes