Malicious PDF — malware analysis report

Static analysis result for SHA-256 c24c57a3c5be4146…

MALICIOUS

PDF

88.9 KB Created: 2021-08-08 15:49:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 07efc20d36afc0d1ac8643a94d9ef685 SHA-1: 471f74c3b31a2929ecaa43df382781d6f8a09bce SHA-256: c24c57a3c5be4146e51266bd8fb121355c0ea3d62ac5e8de998729bccdbf66c7
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics as malicious, including a critical ClamAV detection and a high ML score. It functions as a link farm, with numerous embedded URLs pointing to various websites, some of which are hosted on compromised WordPress installations. The primary purpose appears to be directing users to potentially malicious or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://cructi.ru/uplcv?utm_term=ejercicios+leyes+de+kirchhoff+pdf PDF link annotation
    • http://blpest.com/UserFiles/file/8424565791.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ae188b413---foketefikafegoxematotag.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607aabe443cfe---89705306390.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609d3937a2085---wugatitonorojoliji.pdfIn PDF document text
    • http://poslovniimenik.net/firme_data/files/ranojatefo.pdfIn PDF document text
    • http://www.oteliapelsin.ru/ckfinder/userfiles/files/37269994746.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/c1j3mulvnujc2nik81ip2q4p41/gaxokezemilutafitup.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be08943ac6d---40500745781.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161061678e6931---sedipusiwetitexebeka.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/65nlgab2dfnmn7bl14grr0tlt8/25627862528.pdfIn PDF document text
    • https://airin.lv/images/userfiles/file/lovisafasoxefomefipizibef.pdfIn PDF document text
    • http://ahkkpcm.org/userfiles/ludoludiduwa.pdfIn PDF document text
    • http://creptiles.dk/userfiles/file/27630711581.pdfIn PDF document text
    • http://mpti.ru/userfiles/file/83607207876.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/85040682928.pdfIn PDF document text
    • http://barbusci.it/maisUserFile/file/93942915002.pdfIn PDF document text
    • http://vishwkarmaenterprises.com/webroot/img/userfiles/files/77455636738.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3aeab496b1---53918525111.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608eb11862bdc---sesexasabamuxiwupukuwagut.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608377a6f124b---nogezuzuxata.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/d5f252218af333ef4eed5554a657edfb/25343631463.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/rcnlp4pf9a8n5s41hir84k2ib7/4633960086.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160946015c6563---59521866530.pdfIn PDF document text
    • https://www.elitelawnsolutions.co.uk/wp-content/plugins/super-forms/uploads/php/files/tb368cem6h5amtg54i37qb7sdu/43060440197.pdfIn PDF document text
    • http://ei-windykacja.pl/upload/file/34809927569.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_off0000f520.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF520 17968 bytes
SHA-256: b74d3de5dc08ce1d85ee01bc68e7de32933c2f6edb23cc4b666e63b494177dd0
font_01_sfnt_off000122d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013aeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AEB 10672 bytes
SHA-256: 39fcd24de51086a30f67a67e50616fbe70212ee4e1bfcfa3a6bb06642ac71a47