Malicious PDF — malware analysis report

Static analysis result for SHA-256 b457cea398024035…

MALICIOUS

PDF

99.8 KB Created: 2021-07-20 17:54:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 682efa32c17e3f8301d4c6699d2069ad SHA-1: 5e4f5b243ade8ca586693198d91bb41ad1d31879 SHA-256: b457cea39802403596de4cb23afaa445a69c033ac396d33cdce9f7b6ce6828b6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting it functions as a link farm. These links are likely used to redirect users to phishing pages or further malware downloads. The PDF structure and embedded links are consistent with techniques used to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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 http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0a373641e---vegitiperogibisiwexili.pdf In PDF document text
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/vrkr7dpn29a90sorme8s0q9vr6/55597913574.pdfIn PDF document text
    • http://dolphinkorea.com/files/files/lalatopenazefotulezubub.pdfIn PDF document text
    • https://rachelrom.com/rescontent/file/poxusufow.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/varuvojizura.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/np6qbd494u6vo7manvqt8kj605/fiwenozasagumezekokabate.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/0d93f5cc2f968922f955a97543e6f1ac/69423368892.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073885c444a7---30041506084.pdfIn PDF document text
    • http://nicolalazzarotto.com/userfiles/files/41400120172.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a5deeaba78c---67643151561.pdfIn PDF document text
    • https://noihoithanhtuan.com/media/ftp/file/dirasoweluxebirekivi.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be8248b0aa0---vudibetalorezupuzolabosol.pdfIn PDF document text
    • http://kondicionery-domodedovo.ru/upload_picture/file/2374093201.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b9d78c9a3a4---vejixowupeturulejaxasebip.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16087ccdaa1f35---woritonagejenujudefoki.pdfIn PDF document text
    • http://kentcliffordreunion.com/clients/a/aa/aa84b18e55fac3ff3c25336c5005d9e5/File/ririmividevilepabotu.pdfIn PDF document text
    • https://zoldlepes.hu/userfiles/file/68262086561.pdfIn PDF document text
    • http://icsbc.ru/fuploader//file/6394235617.pdfIn PDF document text
    • http://trekkingsapatours.com/upload/files/dararaseragemu.pdfIn PDF document text
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/78356612da6d048f82ea5afd2b357a89/51174483536.pdfIn PDF document text
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/6c6333d92791dd40e06ec8529bc14b15/6652069234.pdfIn PDF document text
    • https://latework.cz/soubory/movawuki.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-4-30/20210430102519995196.pdfIn PDF document text
    • http://besttailor.info/ckfinder/userfiles/files/sotojofidujesodegipuni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=lyrics+if+i+sing+you+a+love+songPDF 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_off00012322.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12322 17496 bytes
SHA-256: b47ae3b9e7c9c2592a614e5d32d7cd87a05ba6857a3a51acb5e9641d07690d19
font_01_sfnt_off00015140.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15140 10648 bytes
SHA-256: 13d47460c6b750c20a799d3dfdc4f58df720b3f5d5050e6c0ed3a5527e35d89f
font_02_sfnt_off000169da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x169DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1