Malicious PDF — malware analysis report

Static analysis result for SHA-256 5661528c899ce076…

MALICIOUS

PDF

83.2 KB Created: 2021-07-01 09:27:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 88b04cf5c0e992155e3eb7dfb02301d2 SHA-1: 8ae2696514a91b3bd2d9dd2be95d5c0cceabd84b SHA-256: 5661528c899ce076faaae527f00a414d325f19802d26aafefb43effe7e45478f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress uploads and disposable hosting, indicating a link farm designed to lead users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://alexandrapanayotou.com/web/images/static/file/deboburo.pdf
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16091f4bd836eb---nexusutibomadolapuzover.pdf
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607994246db9f---mikanakawepegabal.pdf
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa8a061b58---29817649748.pdf
    • http://consade.com/userfiles/file/90924775933.pdf
    • http://files.ibiza-ferien.de/file/57439282803.pdf
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099ad853c8a6---48644395736.pdf
    • http://avsa.org/sites/default/files/images/files/wigozitebikazomum.pdf
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/ojd6m2ehcrva20bj42a5rt7jfs/5188261586.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607251943ad94---61255524328.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160881b1818f30---vifejaxuwolixozaxejoguk.pdf
    • http://www.naraihillgolf.com/admin/userfiles/file/30376600052.pdf
    • https://kalyna.ua/sites/default/files/userfiles/file/99806414742.pdf
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/bkktsreib2savkuvdu8qkuqu1p/66107341718.pdf
    • https://irantruck.ir/data/file/15639081611.pdf
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160768b2017045---23638779234.pdf
    • http://mitsubishilongbien.vn/images/ckeditor/files/56193923051.pdf
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/denezusikozez.pdf
    • http://paulbwatkinslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/45637406005.pdf
    • https://burmesecatclub.nz/wp-content/plugins/super-forms/uploads/php/files/547d16561d938a14ae2d8871feefc642/87856036677.pdf
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/0b85c44c4b4f0e2866cb1286b182d04a/bofigi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=i+would+like+to+reach+out+my+hand+song
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/27438d39a0b997b8e7c8716edfe1c5a6/jivuvumarojopetel.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e0b3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B3 16792 bytes
font_01_sfnt_off0000f8ca.bin
827ccdae801ec74d489dee58f1a12a75977e4a3cc412eb4b5afee6722de588e6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8CA 11160 bytes
font_02_sfnt_off0001128e.bin
a0113414f96f542a77cf0f560d7ed8c2409034dd5ddf556eda27c596db414e5e
pdf-font-stream PDF embedded font (sfnt) at offset 0x1128E 17420 bytes