Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1976523b3984dfb…

MALICIOUS

PDF

86.3 KB Created: 2021-07-21 15:32:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 4b6b6edf0254912c5d8a6c3e40f9e745 SHA-1: 4f2be9214a8bbf8dd55de8c6e235932b98b4fc66 SHA-256: a1976523b3984dfbf1a30c131cc8eb83bcb43f878c75075bda6017c86f8c85f5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to potentially compromised websites, likely intended to lure users into downloading further malicious content or revealing sensitive information. The presence of multiple links on disposable hosting and compromised CMS uploads suggests a coordinated effort to distribute malicious files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://svazekobciorlice.cz/userfiles/file/tifoxaxumifi.pdf In PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c5c3a5f2bb2---lobazelugik.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16079f836c94a0---28064183172.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160e1669699578---welixupewol.pdfIn PDF document text
    • https://infiniteprospects.com/FCKeditor/file/tewomoneji.pdfIn PDF document text
    • http://smclassof57.org/clients/34860/File/moremib.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/85407622869.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7f44f57096---xiduzujiguzilonapudoket.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/sukenisidanuludenos.pdfIn PDF document text
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/8a3e75044bfadb92dc60d7b938250f26/mufefa.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/f5ce8779deaf7fcebe4be14d32e21de9/nedeki.pdfIn PDF document text
    • http://e-district.org/userfiles/file/fefukukefepefalegopumina.pdfIn PDF document text
    • http://staractivecollection.com/resimler/site/files/zosijixezevafo.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/zurumib.pdfIn PDF document text
    • http://domusanna.it/userfiles/files/bumaxemamuxulole.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608361b00c028---97217755917.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/449b9fa1f6f88fd70631c00e9379147d/rijudavogajekiresawefo.pdfIn PDF document text
    • https://efnnma.org/files/file/41358750312.pdfIn PDF document text
    • http://dd-eng.com/files/files/lesefunasam.pdfIn PDF document text
    • http://grandwatergatehotel.com/upfile_hotel/files/21369100381.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afc11d47b44---65794341697.pdfIn PDF document text
    • https://dienlanhbachkhoa.info/upload/files/37051701903.pdfIn PDF document text
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b780092cd---24110517419.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f50482ed40d---69326818810.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8df1c3dd0e---koxuteredenojonumew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=olex+oxygen+concentrator+manualPDF 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_off0000f071.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF071 10656 bytes
SHA-256: fe2036e043ad70566d77ea1d8f09954b237eda9091bffedea39c910d03837802
font_01_sfnt_off000108f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108F1 16328 bytes
SHA-256: d3e7a1e582c494859e71ace2cff24fda84e073cbe164561880fed048d440bad7
font_02_sfnt_off000132e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1