Malicious PDF — malware analysis report

Static analysis result for SHA-256 523fcf95c6394167…

MALICIOUS

PDF

81.0 KB Created: 2021-06-28 22:17:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 39b70a9fcd415b9ef48b660338601af8 SHA-1: 2aea426fc42bd73cca261ec10993c3a26cbc1a84 SHA-256: 523fcf95c6394167ead1005d2ffc1d4176d1565cd3a9de68fc3041fefe322d73
164 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 WordPress sites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://medvor.ru/uplcv?utm_term=great+is+thy+faithfulness+towards+me PDF link annotation
    • http://capital96.com/userfiles/file/bisomo.pdfIn PDF document text
    • https://skvacations.com/userfiles/file/veliwul.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16077abf99fffa---giwoku.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607943814c9db---12553649955.pdfIn PDF document text
    • http://www.rify.us/cms-uploads/files/78968851604.pdfIn PDF document text
    • http://gold-carsales.com/js/upload/files/44657125564.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce1e1dd6be---saxuwoposenoremevobofapok.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/c111d3ccb5c997d6ab1d0b504f4c76cd/kasir.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/826cb235f61897dbc9cc362ce772ac2b/54845941176.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/3iajvk9p0trq8dmn1j0f549q8n/41186837605.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c32d4e9c6ba---96568353140.pdfIn PDF document text
    • https://toptenstudy.com/upload/files/BodyFile__60D8283F02AFB.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160919913a675e---najipogemotukifovemusibu.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160841a826eac8---papog.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/55652892efb1eab7169f848ffa9ed7ff/59399729711.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9b2d1e6f5f---mamovisateb.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/25621458282.pdfIn PDF document text
    • https://www.bakirkoytemsilcisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160846b2d1df2d---9462456579.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/c8n9pfnjd2hc5dvd7vt79150u4/sujipazumopukunefekon.pdfIn PDF document text
    • http://globalbando.com/DATA/upload/files/202106201545027280.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/44494006985.pdfIn PDF document text
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/47e734d4ef2f85b5c9b5a3a51ab49c91/fuxebif.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ec9da3bf03---87206118497.pdfIn PDF document text
    • https://zegabilisim.com/calisma2/files/uploads/nenunamabozupi.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/5a12027be20cff45daac3d17d1c49114/73032847554.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_off0000d57e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD57E 17788 bytes
SHA-256: 8c160814f56d4a4620ccbf65d3bf9955dd32da612d6c3b54e40727700fc40cc7
font_01_sfnt_off00010396.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10396 10956 bytes
SHA-256: dd7e3b627102406e40f7059964362bc6b2701b0c2aa3f913b17351fcaf1f4ee6
font_02_sfnt_off00011ce8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1