Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cebc6586f65df01…

MALICIOUS

PDF

76.7 KB Created: 2021-09-16 11:07:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ce6551eeecf75dca5bb2a165f23d8e45 SHA-1: 55627cc15a903d90f1653089c0ef46228bdb6101 SHA-256: 1cebc6586f65df01b298437a260b7b6c75b6fa69c66ae03a6a51e32b1cc6a1ec
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and flagged by an ML classifier. It contains embedded JavaScript, which is often used to exploit PDF reader vulnerabilities or redirect users to malicious sites. Several heuristics indicate the PDF is part of a link farm, with many external URIs pointing to potentially compromised or disposable hosting, suggesting a phishing or credential harvesting attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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://samsungdvm.net/upload/ckfinder/files/xirunagurizamolu.pdf
    • http://bualuang101.com/backoffice/upload/files/zebinejonaxarenose.pdf
    • http://smartdeal.pl/files/upload/files/75571444968.pdf
    • https://restaurant-kamkok.fr/img/Data/file/xafode.pdf
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/elt7fmlagrmr3milolhm23im60/sadetaxuwo.pdf
    • https://miraclechuppahs.com/userfiles/file/wogijavunutoveb.pdf
    • https://learningsolution.ca/userfiles/files/xisugopajedafenep.pdf
    • http://hindel-relax.ch/ckfinder/userfiles/files/49939344881.pdf
    • http://portalinmobiliario24.com/uploades/fckeditorfile/3757447270.pdf
    • http://xn--aknmedical-yub.com/uploads/file/38930549544.pdf
    • https://consultemergingmarkets.cubsindia.com/files/78218237273.pdf
    • http://mixmarketing.vn/upload/fck/file/zolamuwozuvajobotozo.pdf
    • http://diplomat2014.ru/ckfinder/userfiles/files/nuwanupalakodij.pdf
    • http://perechen-izdaniy.ru/js/ckfinder/userfiles/files/4547502632.pdf
    • https://rajatotogroup3.com/contents/files/mobupozonap.pdf
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff7b24eea6---22309092655.pdf
    • https://arch.ua/ckfinder/userfiles/files/wadowefaxamukabik.pdf
    • http://matsonconstruction.net/userfiles/file/nuvudavabutamif.pdf
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/d714d3ac56448078b8e008ba409eedef/kuzud.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/12e760fac078d85970dcffac0c794d4b/lepagijapefizapevubufidag.pdf
    • http://elijasprojekts.lv/files/file/dusuduxemof.pdf
    • https://www.tcf.gov.tr/ckfinder/userfiles/files/95449859362.pdf
    • http://goldia.cz/data/file/54948335001.pdf
    • http://kmconlinecme.com/userfiles/file/fobokepapebixaliwavo.pdf
    • https://bocrangsuthammy.vn/upload/files/13349183741.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=messenger+unable+to+complete+request
    • 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_off0000c639.bin
6cab222f5b4c1d4f400089859165915311e7fab761ffc6ca93e2c73aeab77c7b
pdf-font-stream PDF embedded font (sfnt) at offset 0xC639 11004 bytes
font_01_sfnt_off0000df52.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF52 16792 bytes
font_02_sfnt_off0000f764.bin
3befe35f5fd006e1148cf34f69aff1f1865c01616eae29573587e8b50d27a30a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF764 17544 bytes