Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab3b064753c9d2e9…

MALICIOUS

PDF

82.1 KB Created: 2021-09-23 06:28:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 01d8f1c3357feddb034e8684d311d7bc SHA-1: 083841fc49aee0a565eecb62fb836fdff270fec5 SHA-256: ab3b064753c9d2e9b5808d1ad3f48c2df8c8ae91bdb04ec8d51142f19084d160
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, several of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm or phishing lure. The presence of PDF-specific heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://oniceh.ru/uplcv?utm_term=solving+equations+with+ln PDF link annotation
    • https://alpinismbihor.ro/app/webroot/files/userfiles/files/14607062981.pdfIn PDF document text
    • https://braintreeclinics.com/app/webroot/img/files/66262698026.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f1fcf40951---natatabodorulepixoderede.pdfIn PDF document text
    • http://knuhpharm.kr/userfiles/file/20210922054449.pdfIn PDF document text
    • https://oykufestivali.com/ckfinder/userfiles/files/sowixepezek.pdfIn PDF document text
    • http://candleelectricals.com/uploaded_files/userfiles/files/16595813652.pdfIn PDF document text
    • https://fond.ru/userfiles/file/fajazada.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1614085a1b22c3---jemimoxujobub.pdfIn PDF document text
    • http://ballarioarchitetti.eu/userfiles/files/xunakixubototir.pdfIn PDF document text
    • https://al-wesam.com/userfiles/files/pujosatakis.pdfIn PDF document text
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/95736979200.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149a141c244b---7122288507.pdfIn PDF document text
    • http://mrcookie.tw/upload/editor/file/092302156488.pdfIn PDF document text
    • https://10fci.org/userfiles/file/98754994185.pdfIn PDF document text
    • http://kiko168.com/UploadFile/file/20210905124859560.pdfIn PDF document text
    • http://thumpamonpally.com/userfiles/file/53121868638.pdfIn PDF document text
    • https://al-wesam.com/userfiles/files/jirowimeg.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1b65137be---4171158487.pdfIn PDF document text
    • https://timminsrenovations.ca/file/KYzOvVS714WPdmbS.pdfIn PDF document text
    • http://woodlander.sk/grafika/file/finodirekisebevoda.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/42845699192.pdfIn PDF document text
    • 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_off0000d99b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD99B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1AD 18592 bytes
SHA-256: 2fb8dec4a6b00d7b6f827601f57a30d574f04fdab99d7494efcd8c976574039b
font_02_sfnt_off0001226d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1226D 10760 bytes
SHA-256: 94df4db2b88857b0af3d0e405512674bbc80c49008245644b67b39576407dbe6