Malicious PDF — malware analysis report

Static analysis result for SHA-256 6630f37cd6ea85ec…

MALICIOUS

PDF

72.8 KB Created: 2021-09-19 11:54:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4189463b9742fc9233ee016a57b1be5c SHA-1: 22acdf052c13cf8d6eb1faedd89f34bcd23034bb SHA-256: 6630f37cd6ea85ec2fd093aad8b975f1813720ca897043b5c3fb139776e57d50
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and links to compromised CMS upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple links on potentially disposable hosting further supports a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://philabc.ru/uplcv?utm_term=how+to+retrieve+deleted+text+messages+from+android PDF link annotation
    • http://getsolarny.com/userfiles/file/96464747767.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/4dce68c39b7cf77494a57c1e38085e2c/13187914718.pdfIn PDF document text
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/motodejerodadaj.pdfIn PDF document text
    • http://tjchenxing.com/filespath/files/20210910174940.pdfIn PDF document text
    • http://devitohomesorlando.com/userfiles/files/pupewupenuvaluzofegim.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/cq23re0kr4hpk72qv9olk51kgd/sovudisopaxitezeniberix.pdfIn PDF document text
    • http://insureavisitor.com/userfiles/file/nojib.pdfIn PDF document text
    • http://traviet36.com/upload/files/banituwajosojuwasesumo.pdfIn PDF document text
    • http://kibbkw.com/uploads/file/bukifofolox.pdfIn PDF document text
    • http://sportservistocik.cz/UserFiles/File/pemodiridiniwa.pdfIn PDF document text
    • http://asztalosweb.hu/userfiles/file/dawarag.pdfIn PDF document text
    • http://wimborst-ceramics.nl/ckeditor/ckfinder/userfiles/files/38503805697.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1614090eb81460---meruzirajogesewu.pdfIn PDF document text
    • https://bloomland.com/sites/bloomland.com/files/7843030177.pdfIn PDF document text
    • https://chilegastronomia.cl/uploads/userfiles/files/34402394386.pdfIn PDF document text
    • http://aiaato.com/FileData/ckfinder/files/20210916_0215A670B7637C87.pdfIn PDF document text
    • http://phone-server.com/userfiles/file/6579764450.pdfIn PDF document text
    • https://adtw1.elfjane.com/ckfinder/userfiles/files/53534707870.pdfIn PDF document text
    • http://quangcaovuanh.com/vietkiendo/upload/file/zilesorepijisumumoxorudak.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/86670684497.pdfIn PDF document text
    • http://ebd.su/UFD/7623/files/nagiwoz.pdfIn PDF document text
    • http://inkjetartandimage.com/Uploads/file/gotapu.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_off0000ba97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d2a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2A9 16140 bytes
SHA-256: de5c20d8f3d0683b1720cf04f176b66ece371647ede880cf558b7ef12a23e428
font_02_sfnt_off0000fc10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC10 10940 bytes
SHA-256: 92f8eb3eb2097bd89a3d073eee1dfb5c4227e1dca398f5e45f80104e483ca903