Malicious PDF — malware analysis report

Static analysis result for SHA-256 834427255ab27fd1…

MALICIOUS

PDF

71.0 KB Created: 2021-09-29 12:09:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 43180af1c3d458c0cbad7b9b438cfe70 SHA-1: 157fbb138d1444794576da71b89d40b769a7db60 SHA-256: 834427255ab27fd12b24819679f47026a8b77a7a2dcc677a34ed4c7087be249b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The heuristic 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate that the PDF is designed to host numerous links, many of which point to compromised or disposable hosting sites. These links likely serve as redirects to phishing pages or malware download sites, aligning with the ClamAV detection of 'Pdf.Phishing.Trojan'.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://pzhjintai.com/upload/files/14713982888.pdf
    • http://fivelscope.net/fckimages/gomuterojegoxipofijog.pdf
    • http://boras-sjuharad.boj.se/uploads/userfiles/files/movetigomefigevomire.pdf
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/16153c27f6d466---66821415020.pdf
    • http://isystem.hu/userfiles/file/19066975781.pdf
    • http://severstroysnab.ru/userfiles/file/sunukuxefe.pdf
    • https://hotelreviewreserve.com/basefile/hotelreviewreservecom/files/32112970816.pdf
    • http://motoren-adachi.com/js/upload/files/dogagisekifuzisipidababef.pdf
    • https://ap-qatar.com/userfiles/files/wokonasimovufituga.pdf
    • https://neksav.com/upload/ckfinder/files/zoton.pdf
    • http://vrakskodamnetice.cz/file/pulejizeranude.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b7c485df0a---44417194160.pdf
    • https://activepymes.com/pub/file/xetaketane.pdf
    • http://tunesistudio.eu/userfiles/files/togorikejuva.pdf
    • http://bangdinhphucat.com/quangbasanpham/app/webroot/upload/image/files/65367314048.pdf
    • http://kimkhimientrung.com/uploads/image/files/47510389472.pdf
    • http://12shio5.com/contents/files/sipazaboliwawedilokomur.pdf
    • http://aunay-sous-auneau.fr/ckfinder/userfiles/files/xakidipow.pdf
    • https://agape4u.org/userfiles/file/bifajuvolukitak.pdf
    • http://www.herbertvanderbrugghen.nl/draft/wupukixisigup.pdf
    • https://fullgame.hu/uploads/files/jirizegafet.pdf
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/abf66abd24f14443612dfcb7abd471ea/xepebevamo.pdf
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d6cd0b5958---zedefixenowudesenomonevil.pdf
    • http://gezond-trakteren.nl/kasteel-doornenburg-img/bestandenfile/56274943470.pdf
    • http://teplolux72.ru/upload/file/82156870935.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=how+do+i+turn+on+my+email+sync
    • 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_off0000b3df.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3DF 16792 bytes
font_01_sfnt_off0000cbf1.bin
11ac4785f2699aad990b7297dc14f839790a27b06efba096db909441be55ac60
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBF1 16120 bytes
font_02_sfnt_off0000f4e8.bin
036e9a6a569949f82191757d04157b2fdd11d7c37ea07d2dcda2336654338d9e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4E8 10824 bytes