Malicious PDF — malware analysis report

Static analysis result for SHA-256 d23de73d75feb679…

MALICIOUS

PDF

81.2 KB Created: 2021-09-22 20:17:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 784deef47b094f738a64046d99a1ab7f SHA-1: 9134d78c997352b1cc87bb9d1a46e229423a74ca SHA-256: d23de73d75feb679d1d59b6f467f4b72a934789a01a51e38700536c6f51e4124
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for executing malicious code within PDFs. It also features a link farm pointing to numerous disposable domains, many of which are hosted on compromised WordPress sites, indicating a phishing or malware distribution campaign. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • 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://crysiq.ru/uplcv?utm_term=positive+adjectives+that+start+with+y+to+describe+a+person
    • http://abbwingslynnhaven.com/uploads/files/mufovupewasoguxasike.pdf
    • http://ddaengshop.com/ckupload/files/zeforalilegodamoraloz.pdf
    • http://sigmabhp.pl/userfiles/file/35036163617.pdf
    • http://vytvarnyobchod.cz/UserFiles/File/limoremopar.pdf
    • http://boki.hu/editor_up/25818251572.pdf
    • https://vibanghanoi.com/uploads/files/72533070228.pdf
    • http://fairbank-ia.org/admin/ckfinder/userfiles/files/74882719183.pdf
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613361c138353---busuxotilen.pdf
    • https://dienhoanghean.com/upload/ck/files/25275141063.pdf
    • http://flexinform.com/hirlevel/file/1085082352.pdf
    • https://happy-playground.gr/uploads/_uploads/files/zixosujuxesoxuxorenupel.pdf
    • https://huaienclinic.com/uploadpic/files/51264007623.pdf
    • http://www.gobarging.com/uploads/textareas/file/71359196769.pdf
    • http://www.mananthavadynorbertines.org/www/js/ckfinder/userfiles/files/jakumu.pdf
    • http://strategie-online.net/catalogue_dynamique/file/48977605039.pdf
    • http://cluboutletmoto.net/campannas/file/jidejowugowamof.pdf
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/60e8a67ad7fab301bc8c93e38818a1bd/rodefuwuvidu.pdf
    • http://orderbestwings.com/uploads/files/21678414315.pdf
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144bc85e1e7f---porikudikuxone.pdf
    • http://studiolorenzino.eu/userfiles/files/bupixilewodelusad.pdf
    • http://leguido.net/files/jodusuw.pdf
    • http://studio70.eu/userfiles/files/jovutokixeranakelagafawi.pdf
    • https://optimustelecoms.com/ckfinder/userfiles/files/lepabofukavemuvavajo.pdf
    • https://coolinterier.sk/upload/files/15032297339.pdf
    • http://sanfrancescovet.com/userfiles/files/58537269937.pdf
    • 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_off0000d635.bin
c8b49fe229321c206a27659da1653e3772117fc193da0b5061ac927f0187ba02
pdf-font-stream PDF embedded font (sfnt) at offset 0xD635 11104 bytes
font_01_sfnt_off0000efe4.bin
49aa0adadf44c9c89ddd089c0b89017611f04b2d45020109bb76976a4ffcc1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE4 18340 bytes
font_02_sfnt_off00011e88.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E88 16792 bytes