Malicious PDF — malware analysis report

Static analysis result for SHA-256 7673556f10266631…

MALICIOUS

PDF

75.9 KB Created: 2021-09-02 09:58:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 5c8d7c98f98e58d6510ad32ca9e547b1 SHA-1: 862df7db119a6bf597679ba9682045c36722b3ae SHA-256: 7673556f10266631d5d39036e897b6f94d1e85979f067a5d0d0b77808fa87bd4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The embedded URLs and the PDF structure indicate an attempt to disguise malicious content as legitimate links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 6

  • 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.
  • 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://bucketdiaries.com/uploads/files/2334644022.pdf In PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dcca049b25---sixikamivovonajavigawazul.pdfIn PDF document text
    • http://sriraghavendratemple.com/ckfinder/userfiles/files/piminupuzex.pdfIn PDF document text
    • https://tecnicadovolante.com/images/file/minubelaje.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/jerepugobaxukoguzar.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160987233c0edf---lokeratipikelakorotot.pdfIn PDF document text
    • http://flyingkirin.com/uploadfiles/file/310053327349.pdfIn PDF document text
    • http://megalaserasia.com/upload///xotoxuxirasofutakebik.pdfIn PDF document text
    • http://markone-tools.com/upload/files/jurugolimigu.pdfIn PDF document text
    • https://sarenpinler.com/calisma2/files/uploads/90629987143.pdfIn PDF document text
    • http://php-lounge.de/userfiles/file/58542693974.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/pemukakaboranonig.pdfIn PDF document text
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/61e47097a1e557f3e6fed413f17b4696/diwutebupun.pdfIn PDF document text
    • http://studiogalata.it/userfiles/files/48123913131.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082e623b5e8c---6805314520.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a69cbc5d43c---96023188788.pdfIn PDF document text
    • https://shop-ecobati.com/medias/upload/files/jumabari.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/94039304018.pdfIn PDF document text
    • https://augsburger-dartliga.de/uploads/file/rigurubofikivawumenutuke.pdfIn PDF document text
    • http://edanieltour.com/FileData/ckfinder/files/20210624_A115D69BCF7EA795.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072178b78eb9---rixadotonimido.pdfIn PDF document text
    • https://godparents4tz.org/home/god/public_html/ckfinder/userfiles/files/lalasiku.pdfIn PDF document text
    • http://raylutickenterprises.com/userfiles/files/nefuxuveparidizepukabu.pdfIn PDF document text
    • http://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/roliduduni.pdfIn PDF document text
    • http://bulmarconsult.com/files/pukezimenu.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/b267db0181e959c6862017ec6d16d49c/39597008159.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=roblox+one+piece+gamesPDF 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_off0000c45a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC45A 17268 bytes
SHA-256: dcbd0b7516ae1510add5830970f39a31051c93e304672c0d663c9ce758fbf58e
font_01_sfnt_off0000f09b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF09B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000108b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108B2 10808 bytes
SHA-256: b9e235c6e447b5b070dd0a16f7a1108e958dfc82747426ac6c31177923f9ba8b