Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2c3df735786b379…

MALICIOUS

PDF

86.3 KB Created: 2021-07-04 02:21:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 4682380c1b3ec486276909eaa320c4a8 SHA-1: a64451cb41ed98c9de0d471a0889f66d1780c27f SHA-256: b2c3df735786b379d6194022270a6aaee5e7a126aa562a14d5770cd554a54d98
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristic analysis revealed it functions as a link farm, directing users to multiple external URLs, many hosted on compromised WordPress sites or disposable domains. The presence of numerous links and the use of UTM parameters suggest an attempt to distribute phishing content or download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • 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.
  • 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://smidgel.ru/uplcv?utm_term=mpre+practice+questions+and+answers PDF link annotation
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160772384b9857---kegomototisazeloxo.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a27f02a003c---jepilefizojafefexef.pdfIn PDF document text
    • http://inventory-acepipe.com/images/uploads/files/gapovofawebazasel.pdfIn PDF document text
    • http://rolfingnaples.com/clients/a/a5/a5422f62036d2d393d866963e902351c/File/wotutewi.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/91tf9eqnacq76n0rb5ba4tql34/zelolelakikiketureb.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079e25208aac---vikimani.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/487d68ce7fb5b862b3299091798d0f9e/50903022916.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16077ca3ae970d---raxalatogijibes.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/160bd6e34c74f6---tirekodadedosek.pdfIn PDF document text
    • https://autoandtruckrepair.net/nbloom/fckuploads/file/89231144859.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/72853935829.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090153cec72c---mimubi.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160aef91326ae6---69526505892.pdfIn PDF document text
    • http://sriagasthiyarastro.com/FCKeditor/userfiles/file/90033576866.pdfIn PDF document text
    • https://bawwabatrizq.com/userfiles/file/5686394035.pdfIn PDF document text
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/9307099073.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/cq9h2mhjusscu9tmn9bfefv6h1/bemimesazutomovoji.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/447184ed51836a6ca1c5583ac575225f/gavezef.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/g83enmt68gqr2bj5cam8crb78e/monuwesinebe.pdfIn PDF document text
    • https://mudraconsultancy.com/uploads/files/6947203584.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/160848ce3345b7---fejenotavi.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/0rn908uit0q6ko6as4nufqvg0e/gugupeju.pdfIn PDF document text
    • https://mcq-exambd.com/app/webroot/ckfinder/userfiles/files/65179390352.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cec0af5bd84---rinimonumarom.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_off0000ece2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000104f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104F9 10784 bytes
SHA-256: f4c8515034a6c82e6f15010eb72a04603a89aa17813277b7d344e9fc40df0a1c
font_02_sfnt_off00011dce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DCE 17488 bytes
SHA-256: 6fe3d2b04164775b8e9bb92f158b29693bca710c37bebe95f8a35322ef922e16