Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4d990fa31ffc21b…

MALICIOUS

PDF

80.4 KB Created: 2021-09-05 12:17:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 63582d49b2efa9cd8df40d724fb4cf87 SHA-1: b38436bde1a9811993852c69b3f5058dcda79c91 SHA-256: c4d990fa31ffc21bb223b3ddf4397b4bd065cdcb4eab3cec097cf354b7991c05
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 acting as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://robinio.de/wp-content/plugins/super-forms/uploads/php/files/0ans0bdcba912t86en9sekjquv/94944407212.pdf In PDF document text
    • https://2ruoteexpo.it/ckfinder/userfiles/files/bugizi.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087d8ff2f445---xuzubupivar.pdfIn PDF document text
    • http://effektfilm.de/files/file/4445683913.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d66d7783c83---vogigize.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160859c610d740---28053872004.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/825c35941f90f076616b800e4a237426/45957344693.pdfIn PDF document text
    • https://matfreklam.com/calisma2/files/uploads/mojesiliduzi.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/2563ea97c759860a70c6fdb3054b3e9b/zurotufojekami.pdfIn PDF document text
    • http://bbpcosmetics.com/admin/upFiles/2021-5/file/fijefuguvol.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606c91965d662---41766493715.pdfIn PDF document text
    • https://mattress-leader.com/media/13266961837.pdfIn PDF document text
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606cee9e250a0---rimoze.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/59954118827.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/43322142570.pdfIn PDF document text
    • http://familiegravesen.dk/ckfinder/userfiles/files/86281470587.pdfIn PDF document text
    • http://nguyenthaotech.com/upload/files/4177854743.pdfIn PDF document text
    • https://francois-daulte.com/ckfinder/userfiles/files/38269977683.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/0n2d4cf4f38bi59l7r2k2q469n/nosonipupoj.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/9dfd35515f73f68d1ae3ce97aee94c66/76889357981.pdfIn PDF document text
    • http://aceonlinementors.com/userfiles/file/3568311023.pdfIn PDF document text
    • http://quimis.org/js/ckfinder/userfiles/files/51336674477.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160e58547568fb---pibexenebakamujozeta.pdfIn PDF document text
    • https://argentinaproduct.com/ckfinder/userfiles/files/guzixitiposokifuvaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=singer+sewing+machine+manuals+vintagePDF link annotation
    • 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_off0000d642.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD642 17332 bytes
SHA-256: b2c3a5408b4de2bc00b9551d17dd29dfba0ba8ea7f89ef13f9819d447bad6b1e
font_01_sfnt_off00010300.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10300 10884 bytes
SHA-256: c6bf45562b9d4e1b6a2ed2e884b5b36477d18fb67925cb237af7bf115669a416
font_02_sfnt_off00011c05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C05 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1