Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3c1261feffdefba…

MALICIOUS

PDF

79.0 KB Created: 2021-09-06 01:02:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 236485c579380e05bfdc39bc8df1b73a SHA-1: 03f17c858467a6d80241e917755ec70ce20737b2 SHA-256: e3c1261feffdefba558b22a626350fd194b87614d60e2726a56fc7d7b3b54110
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and other domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The heuristic firings related to link farms and compromised CMS uploads further support this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://allytemp.ru/uplcv?utm_term=novel+hans+risa+saraswati+pdf PDF link annotation
    • http://bugaboo-buffalo.eu/UserFiles/File/16668593836.pdfIn PDF document text
    • http://heorungminhphat.com/luutru/files/tubeliburitixubazun.pdfIn PDF document text
    • http://sunrui-ti.com/d/files/dufalegat.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/nivogute.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/tetinifinonorusebukep.pdfIn PDF document text
    • http://cuatudongsaigon.net/uploads/files/10774997874.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/6c3af5e53f16abd3fd8ea48a235579bf/14191416793.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/16764368645.pdfIn PDF document text
    • https://advantagelic.com/singhania/downloads/file/5950981494.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/vo118pl2lapdpkdbncqjkt3tm7/70467016982.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/fgphpnrftlk66i2oq1cktu576v/96303457199.pdfIn PDF document text
    • http://1960ihs.com/clients/e/e0/e0b58928a48036c9af8d6cfc9cffdd99/File/50662228089.pdfIn PDF document text
    • http://moscowprice.com/content/xuploadimages/file/beron.pdfIn PDF document text
    • https://baongochoa.com/upload/file/36284075138.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16085d92f50b38---xozodu.pdfIn PDF document text
    • http://szentimresiklos.hu/upload/file/65885356737.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9718e00b9---janabefetoliliwofama.pdfIn PDF document text
    • http://rogo-rotterdam.nl/files/59924158191.pdfIn PDF document text
    • https://agencement-menuiserie-var.fr/stockages/files/sorerijetotepaxatigiwa.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/2299a9dd8da1f6cc49df931ccbee7b13/bidojirinazirobeloderew.pdfIn PDF document text
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/fdfb507cc1d99e137ad4f5ea18b618d7/87380574256.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_off0000d21c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD21C 10724 bytes
SHA-256: 1bb524ce1e961844d2334f7bf052a8c2d7cf55bbac51999fb7a381ce1aee89b2
font_01_sfnt_off0000eabf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEABF 16960 bytes
SHA-256: 10977e55ae8ccd9b1cb6e31082b749d3b52eb2c36758ccd78c6e673cb79a6b4f
font_02_sfnt_off0001169f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1169F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1