Malicious PDF — malware analysis report

Static analysis result for SHA-256 660cc5137ef63a78…

MALICIOUS

PDF

91.2 KB Created: 2021-06-26 11:42:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 92c198bb87b53d7073c008418b9a17d0 SHA-1: ba235eed596eb1c25ada7c3b2c58b1840a1b5a2a SHA-256: 660cc5137ef63a78e78d9d350cb4d470c8b8a872b37b146146f7816bbec02ce3
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF contains embedded JavaScript, which is often used to redirect users to malicious websites or download further payloads. The document body is heavily obfuscated, but the presence of external URIs and link farms pointing to compromised CMS uploads suggests a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://huntic.ru/uplcv?utm_term=calculus+with+differential+equations+9th+edition+solutions
    • http://angarakshaksecurity.com/userfiles/file/wenonibab.pdf
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086a9db8cd14---98351058996.pdf
    • https://sport-jicin.cz/dokumenty/pozazave.pdf
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/tc3bn3oo17ai4fev15ia8oigta/12472155625.pdf
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/q14rs88d0riffkttnuov3ad122/nidewukusujaveseni.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1607150aa9a483---57759005839.pdf
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b334121bc11---90996801911.pdf
    • http://aryajob.com/user_upload/file/gevuper.pdf
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/zusazonejurefuzup.pdf
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//15192395938.pdf
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b52bc4f1070---tonajujidolixu.pdf
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/s9ibd1vrubrq7k4rv2m1hek8oa/65343689121.pdf
    • https://pametnidom.hr/pametne_kuce/userfiles/file/75524095769.pdf
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607369adcc324---49209008326.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c8bc5516ee3---87253495385.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160838033591ea---1333896058.pdf
    • https://fruzsiflame.hu/userfiles/file/23802125876.pdf
    • http://maduraicaterers.com/app/webroot/js/ckfinder/userfiles/files/39198576644.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/218d45dc4069f7f32782e365c3754003/6871658313.pdf
    • http://arcomproltd.com/userfiles/file/rojovixupoza.pdf
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/978489891859a40a2bc2e69892c3adab/57497980210.pdf
    • http://xn--zb0bw3kv4s8mn.com/upload/fckeditor/file/44793567646.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094c66b50793---19355550229.pdf
    • https://hgb.se/filer/file/23321245421.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_off0000fa72.bin
f5be17de932691100c4a2b2d4f65278b278e70e67bd25d7fbde141d6997fd829
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA72 11104 bytes
font_01_sfnt_off00011437.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11437 16792 bytes
font_02_sfnt_off00012c49.bin
5c319794cc7b253b130538b0e0dbd6a0edca73a398d51a805f7640a90eca793b
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C49 18888 bytes