Malicious PDF — malware analysis report

Static analysis result for SHA-256 61646000141a3946…

MALICIOUS

PDF

76.7 KB Created: 2021-09-18 04:52:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: cc882f510a8ddb7596f499a2ac8b02d6 SHA-1: 7078d4df1d1c16e25a05946486044158fa0fc5dd SHA-256: 61646000141a3946076795a3aba0cf6eb45b97e3c4d6995cc8686aac9e6e4bfe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to disposable hosting or compromised CMS upload storage, indicating a link farm designed to redirect users to malicious sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://csc0512.com/userfiles/file/20210915210544_zs6yzy.pdf In PDF document text
    • http://banglatalkies.com/dynamic-images/cms/file/39237073414.pdfIn PDF document text
    • https://bloc-immo.com/images/wavikewolovano.pdfIn PDF document text
    • http://lifecare4all.com/upload/files/fozogebuluv.pdfIn PDF document text
    • http://friulanapanini.com/images/file/26818117431.pdfIn PDF document text
    • http://nenorm.com/files/files/fufowegudurebi.pdfIn PDF document text
    • https://www.serwkom.pl/plugins/ckfinder/userfiles/files/5432696003.pdfIn PDF document text
    • http://eros-arena.com/eros/userfiles/file/kizugulip.pdfIn PDF document text
    • http://redemaisfarma.com/userfiles/file/kobixodevemogin.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/hsbd7muh40mb2gem2gnqkkupk9/sobotalegilenajesedisojev.pdfIn PDF document text
    • https://indiansecuritisation.com/ckfinder/userfiles/files/wujedafetu.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/sabepokovagosanazoxam.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137516b8994e---kuremarojeri.pdfIn PDF document text
    • http://nitexprofi.cz/userfiles/file/75876207899.pdfIn PDF document text
    • http://kramnyca.info/img/upload/editor/file/47753318861.pdfIn PDF document text
    • http://hsound.ro/images/custom/file/fodudisuvi.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161412d07114c3---zalometifuwamedowalakam.pdfIn PDF document text
    • https://distriparkbotlek.nl/userfiles/files/11676091819.pdfIn PDF document text
    • http://sunmoon-glory.com/web/upload/files/nebudokig.pdfIn PDF document text
    • http://rld-carbon.com/file/11956082288.pdfIn PDF document text
    • http://customize.fr/fckeditor/editor/filemanager/connectors/php/img/Editor/file/11542668336.pdfIn PDF document text
    • http://pm-property.pl/userfiles/file/wowuwugerefura.pdfIn PDF document text
    • https://xebecdesign.com/xebec/userfiles/file/90012705466.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=how+do+you+change+the+password+on+your+phonePDF 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_off0000c5be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5BE 10948 bytes
SHA-256: 1e59df5f1ce7b886eaa3a9c9b22450c20a462fc5ad3fe6fce8c8f0581a7484dd
font_01_sfnt_off0000deec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEEC 17808 bytes
SHA-256: 6bab26429607635a3636a7a63a0075312023f3ce6bac5e3fd043ce978b926f87
font_02_sfnt_off00010d0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D0A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1