Malicious PDF — malware analysis report

Static analysis result for SHA-256 716661fb09579891…

MALICIOUS

PDF

84.0 KB Created: 2021-09-21 03:52:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 61a83dd7dbba4804047e363fa56c6d18 SHA-1: 4322c8a7ed3909b3fde17aa64e75a2fe203d8caf SHA-256: 716661fb09579891558e4407ff0d57a54bc354f274653a0d17bd4eb589b14ae0
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or are part of a link farm. The ML classifier strongly indicated maliciousness. The embedded JavaScript likely facilitates the redirection to these external sites, which are used to obscure the true malicious intent, possibly for SEO manipulation or to host further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9945

Heuristics 6

  • 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 https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/8fd2846b97a4472817ee71d87e0acc30/55819048412.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140d95cc7ff2---41977127374.pdf
    • http://deforma.it/userfiles/files/taleselod.pdf
    • http://worldofpacifiers.com/editor_uploads/system/files/92813842711.pdf
    • https://konferencii.ru/js/ckfinder/userfiles/files/9747158702.pdf
    • http://kerrya.com/ckfinder/userfiles/files/90158447731.pdf
    • http://travelsi.ru/ckfinder/userfiles/files/97658343422.pdf
    • http://zamel2.pl/userfiles/file/lawimopisimovavenajibe.pdf
    • https://samavetpharm.com/userfiles/files/vawiwukikakimi.pdf
    • https://stormester.no/files/file/71108176231.pdf
    • http://premiumcsp.com/uploads/files/dexoforuja.pdf
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/161371b0413040---jefetekuruwi.pdf
    • https://praktijkbinnenstad.nl/file/82758524712.pdf
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613fa21aa2445---51531110854.pdf
    • http://umrllc.com/userfiles/files/zedilefol.pdf
    • https://nodka.eu/ckeditor/ckfinder/userfiles/files/40222920040.pdf
    • http://sea-cruise.ru/ckfinder/userfiles/files/wolexavodevo.pdf
    • http://kietminhrivet.com/upload/files/69296566242.pdf
    • https://flammerouge.ch/userfiles/files/duwanoraxojuxuwobov.pdf
    • http://farmaciafici.com/userfiles/files/61333762953.pdf
    • http://dagmare.de/userfiles/file/wuginadenadom.pdf
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147db07461f3---12997828364.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613007d4c0284---pojegewanirufe.pdf
    • http://iwort.de/userfiles/file/6835905929.pdf
    • http://porpora.info/imagenes/imagenes_contenidos///xijotumusoxemopotare.pdf
    • http://artdealer.vn/upload/fckimagesfile/0bcc26e5e84e5a3abe456c572631b0ed.pdf
    • http://litho-and-co.fr/ckeditor/upload/files/12597075841.pdf
    • https://ls-machinery.com/uploadpic/files/202109070156596372.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=this+is+us+season+1+123movies
    • 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_off0000e124.bin
d6c9b894613dd6eaa3f462f5301dfe792e6abab43ce5873cb75f02319612b9de
pdf-font-stream PDF embedded font (sfnt) at offset 0xE124 10604 bytes
font_01_sfnt_off0000f94c.bin
73b8ba39bb39511da57911c64e58c4eedf3cda3dae8d863b959fcf9c6a267468
pdf-font-stream PDF embedded font (sfnt) at offset 0xF94C 18444 bytes
font_02_sfnt_off000129da.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x129DA 16792 bytes