Malicious PDF — malware analysis report

Static analysis result for SHA-256 271619e6ff23465d…

MALICIOUS

PDF

86.5 KB Created: 2021-09-16 10:03:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b92df28eeb8384d9ef0854c7621858bc SHA-1: 96c1ca1f766de47b976bd619b0fc972f89034017 SHA-256: 271619e6ff23465d5454f863812eda74f52538c5efd6829bee5e557c8fc30a0a
156 Risk Score

Malware Insights

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

The PDF document contains a link farm pointing to numerous compromised websites, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://krossi.ru/images/content/files/77395312836.pdf
    • http://faceconnects.com/ci/userfiles/files/92613943327.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613a92aa8ba80---sugexewixerulur.pdf
    • http://champagne-marc-chauvet.com/images/files/91280435474.pdf
    • https://electrodomesticaruano.com/images/ckfinder/files/89490575128.pdf
    • https://psiakocky-potisk.cz/webpagebuilder/ckfinder/userfiles/files/53118503866.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134792dd6cab---70841492161.pdf
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/mjfbeepen58g8ckosn6baa417l/moforibuvesulelegorad.pdf
    • http://ibtaker.ps/userfiles/file/65052644871.pdf
    • https://hebatkeren88.com/contents/files/vipexuzikovotep.pdf
    • https://daks-96.com/f/uploads/files/nisisagenapago.pdf
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161387535e6162---27568457703.pdf
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files/baxos.pdf
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/a4ssnas0rchbe5jvbloild6cq7/56386990114.pdf
    • http://ritadas.in/userfiles/file/wodovupazijodesuzojijaxow.pdf
    • http://buyyoutubesubscribers.com/ci/userfiles/files/72647599961.pdf
    • http://www.europesolidaire.eu/userfiles/files/nebimekewas.pdf
    • http://indianspringhomes.com/userfiles/files/70514162293.pdf
    • https://uleshuzataruhaz.hu/files/file/patuwomulul.pdf
    • http://szolnokepul.hu/userfiles/file/wizalefidasaxu.pdf
    • https://deltaguvenlik.net/userfiles/file/93731574162.pdf
    • http://bangdinhphucat.com/quangbasanpham/app/webroot/upload/image/files/gufowuvagawowim.pdf
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/v621uhu0chchroq40qgb6tjc2g/vidafesenazumov.pdf
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161416256b2ff7---67846091990.pdf
    • https://studybrilliant.online/app/webroot/img/userfiles/file/panusovetiseriluv.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=android+display+name
    • 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_off0000efc2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC2 16792 bytes
font_01_sfnt_off000107d4.bin
15acf3efbd3853c537fa75be67c0d6405b9d46990da1bde553700f874cd90f50
pdf-font-stream PDF embedded font (sfnt) at offset 0x107D4 17208 bytes
font_02_sfnt_off00013494.bin
de86feb30eb8aa2455a77d891801c0cd36cbe659888c9a793621bf1c4816b592
pdf-font-stream PDF embedded font (sfnt) at offset 0x13494 10548 bytes