Malicious PDF — malware analysis report

Static analysis result for SHA-256 e51b54f355188fbc…

MALICIOUS

PDF

101.7 KB Created: 2021-09-12 21:01:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f534d3f3df3d592780ba10067b9e8f4c SHA-1: dac3fe136ecd99603441e31f568d15dc805f8871 SHA-256: e51b54f355188fbcd4580aefbac865a5e7af18c9ac9c16fa49f77aba982cdbc1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous embedded URLs, many on disposable domains and using UTM parameters, strongly suggests a phishing or malware distribution campaign. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9803

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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=manga+mew+apk PDF link annotation
    • http://hydrogears.com/survey/userfiles/files/53983171560.pdfIn PDF document text
    • http://dietmoiquangle.com/webroot/img/files/xojufamale.pdfIn PDF document text
    • https://tepihtrava.rs/files/16284554655.pdfIn PDF document text
    • http://ugrctrani.it/userfiles/files/nerovomi.pdfIn PDF document text
    • https://dmitrovka-zn.ru/admin/ckfinder/userfiles/files/15971621430.pdfIn PDF document text
    • http://ijdssymposium.eu/upload/99473925757.pdfIn PDF document text
    • http://studiosiriosrl.it/userfiles/files/73368428717.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/zugofimalakereniduzoxoke.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/20726cb595b7d8a8cd69e8c8e46ecfa9/40690854030.pdfIn PDF document text
    • https://digireg.es/upload/35535656061.pdfIn PDF document text
    • http://pyhunlian.com/uploadfile/file/gevudu.pdfIn PDF document text
    • http://annabarons.lv/files/files/4997589313.pdfIn PDF document text
    • http://www.grupoaccs.net/ckfinder/userfiles/files/20143980582.pdfIn PDF document text
    • http://mezon.jp/userfiles/file/gaputasavetitamoxopuk.pdfIn PDF document text
    • http://webcertain.ca/contentupload/fckeditorUploads/organization_/file/96652656642.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba60d7e622---36740688772.pdfIn PDF document text
    • http://cachnhietcacham.vn/Images_upload/files/40426115338.pdfIn PDF document text
    • http://tv-kitchen.ru/files/files/xozekawep.pdfIn PDF document text
    • https://ezgoe.com/10005001208290177/ckfinder/userfiles/files/2956227159.pdfIn PDF document text
    • http://iowatriallawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/35073233107.pdfIn PDF document text
    • https://apatity.verlauf-ekb.ru/admin/ckfinder/userfiles/files/pekupeleweguvomitet.pdfIn PDF document text
    • https://debo-fit.be/userfiles/file///51649627003.pdfIn PDF document text
    • http://brandweeramsterdamamstellanden.nl/userfiles/file/mapujosivu.pdfIn PDF document text
    • http://infosierra.es/images/editor/fevijodivanoxitomu.pdfIn PDF document text
    • https://biorenta.lt/ckfinder/userfiles/files/gezivozevitizero.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/24036125287.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_off000127db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127DB 10140 bytes
SHA-256: ea6efec78d6192a8ca03eb8e16dcb97674dae583469d0571afb85b5a1b994e86
font_01_sfnt_off00013e84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E84 19160 bytes
SHA-256: f25c5cdc52afac2b14795c4b6fc955fd9eeab2f7bd76cbc80c9e865aa9bad8f3
font_02_sfnt_off00017056.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17056 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1