Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9f196b5f483380c…

MALICIOUS

PDF

84.6 KB Created: 2021-09-18 21:30:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 0fafb8b0a72c4bc2b77e1eee55783a1c SHA-1: ff43e2bd1ef218fd71799bb553c2d757cba967ba SHA-256: a9f196b5f483380c2a654f81acaa0fa3c92e2e96a909544c798e0d21af4432b9
124 Risk Score

Malware Insights

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

The PDF file was detected as a phishing trojan by ClamAV. Static analysis revealed it functions as a link farm, directing users to multiple compromised WordPress upload storage locations. The document body is heavily obfuscated and unreadable, but the presence of numerous external links and the ClamAV detection strongly suggest a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier clean score 0.2364

Heuristics 5

  • 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
  • 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://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161457934c99b4---somavejagebowub.pdf In PDF document text
    • https://inijariku.com/ckfinder/userfiles/files/fazafixixagojodopibuka.pdfIn PDF document text
    • https://olterus.info/contents/files/8633034917.pdfIn PDF document text
    • http://studioarclab.eu/userfiles/files/93050025195.pdfIn PDF document text
    • http://biblioteka-belzec.pl/upload/files/fuleviresubowisu.pdfIn PDF document text
    • http://kxnjl.com/userfiles/files/xoluruniwuvezaribib.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/161415007302d5---16097096601.pdfIn PDF document text
    • http://lukoilmarine.com/ckfinder/userfiles/files/wepebi.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/morimalefojuk.pdfIn PDF document text
    • https://soroptimist.be/oldsite/intranet/ckeditor/ckfinder/userfiles/images/files/xugaxajusokex.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/161457ead619c9---wojulesotejexuzadisokiw.pdfIn PDF document text
    • http://xn--o39a91gvwm83kbsn.com/FileData/ckfinder/files/20210919_21FBC1EA901F622A.pdfIn PDF document text
    • http://meskerjager.nl/media/files/51880340105.pdfIn PDF document text
    • https://calienglish.com/ckfinder/images_store/files/vojexozel.pdfIn PDF document text
    • http://infoegrafica.com/userfiles/files/4906973301.pdfIn PDF document text
    • http://clinivetmadonnadirosa.eu/userfiles/files/16557846388.pdfIn PDF document text
    • http://speckrepej.com/upload/file/fajomufakimetuvasebif.pdfIn PDF document text
    • http://electronicaindex.nl/images/uploads/duzuvije.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614082bf1299a---37424787660.pdfIn PDF document text
    • http://aurora-c.jp/files/files/zepitabibelujiviza.pdfIn PDF document text
    • https://diarch.in/WYSIWYGImage/file/23294554122.pdfIn PDF document text
    • http://originalbau.hu/imagesfiles/25601410424.pdfIn PDF document text
    • http://flooroverstock.com/admin/userfiles/file/rokeropobexobilagemeba.pdfIn PDF document text
    • https://fminterativa.net/cms/plugins/ckfinder/userfiles/files/19522850467.pdfIn PDF document text
    • http://zechnerbau.at/images/content/files/nilepaxoxun.pdfIn PDF document text
    • http://xn--80aiddhbkcq5bcaz.xn--p1ai/upload/files/naponoderajarovatole.pdfIn PDF document text
    • https://www.osteopathe-montpellier-sud.fr/ckfinder/userfiles/files/durekenunaloma.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=how+to+make+notifications+light+up+lock+screen+androidPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f78b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF78B 11336 bytes
SHA-256: 6809984f3276b47568066f3cbb398ec0a0bd8e237a8dee307bdd884f371339f9
font_01_sfnt_off000111d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1