Malicious PDF — malware analysis report

Static analysis result for SHA-256 271aa68a5e48438e…

MALICIOUS

PDF

78.4 KB Created: 2021-09-03 19:17:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ba53b3d8bbdcf753798f7f4ddced378a SHA-1: 51cf2532bdb50b4c07267fbe8f8e9c49d8d6be2c SHA-256: 271aa68a5e48438ec2bad80386554c2afc7a599b87451b389eaa6dd8276eb5ff
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple external URLs, many of which are hosted on compromised WordPress sites or disposable domains. The primary goal appears to be redirecting users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/o3cag6a9arvpv2to20iv3odmbj/49177049714.pdf In PDF document text
    • http://zkojicin.cz/userfiles/file/21849561424.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/16085a27899861---34046073409.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/e0235dd1b48d6710f68c478176382c7c/todonukiwowigoze.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/gakegujivanavaroda.pdfIn PDF document text
    • http://tamlaproject.com/userData/board/file/67392921008.pdfIn PDF document text
    • https://stockbauer.hu/uploads/file/dagabajo.pdfIn PDF document text
    • http://elmbbq.com/uploads/files/82021613977.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/48d609292f51705228f95dcd3fe2efd4/2133832736.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/28834410723.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/vokewagur.pdfIn PDF document text
    • http://shelton1961.com/clients/35589/File/meperajen.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/60dfc326db448676ec55aeef843de517/57451497843.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b2dac407346---gukovebifizuvemo.pdfIn PDF document text
    • http://imbirimbir.ru/files/55511392003.pdfIn PDF document text
    • https://ficsllc.com/wp-content/plugins/super-forms/uploads/php/files/53ct85vdj3ohj63t2bm0a3flv2/28638776985.pdfIn PDF document text
    • https://fulzugaskozpont.hu/files/79986845492.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/cf69d46983be42b97f370495556cfee6/16353712849.pdfIn PDF document text
    • http://geose.ru/userfiles/file/lapokar.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607de4adc043f---sijesapaxukotutixiwer.pdfIn PDF document text
    • https://chambredhotes-savoie.com/ckfinder/userfiles/files/74384801652.pdfIn PDF document text
    • http://bulk-supplies.com/userfiles/file/36525777898.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/ebcnc19e599m7li14jggih323a/80855873438.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607016cf787d4---bedugepapamu.pdfIn PDF document text
    • https://strechybenesov.cz/content/kijakalevorovu.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e373eb29a65---18109814091.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=number+1+worksheet+for+preschoolersPDF 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_off0000ceea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEEA 10832 bytes
SHA-256: 0d4155b17f75c8dd2af80ef0b2a438bfb0661ce9769a60127786f021aa368565
font_01_sfnt_off0000e7dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7DC 17096 bytes
SHA-256: 44c9f836c06959cffe207f933f6b1604437e9514e58367d39d7163bb64fa144f
font_02_sfnt_off00011427.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11427 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1