Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b07e78138d93431…

MALICIOUS

PDF

71.3 KB Created: 2021-09-28 19:22:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fb901758389cd6810ac89d73a4762ab7 SHA-1: 24906aedcd35b8e1620d52cd8aaf2ccdc2c122be SHA-256: 5b07e78138d93431cbd96a0cfde478a71aebf786b5037d2be527b0fe47e918ce
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which are part of a link farm hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The embedded JavaScript is a common method for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cructi.ru/uplcv?utm_term=macos+set+android_home
    • http://xn--80aer5aza.xn--19-kmcm3c.xn--p1ai/ckfinder/userfiles/files/9026038328.pdf
    • http://phunggia.biz/userfiles/file/tazudeweko.pdf
    • http://pamatudarbai.lt/ckfinder/userfiles/files/53216287205.pdf
    • http://kovovyroba-nosniky.cz/UserFiles/File/92825922747.pdf
    • https://garraldaarquitectura.com/garralda_userfiles/files/rikuv.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161364c3c19715---rigoze.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/0alu7gvv593p6jphfl715ru2m1/97614737376.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/4qhuojmhh14hk6jvbegak2gvok/73931469162.pdf
    • http://to-kajihan.net/js/upload/files/41823946928.pdf
    • http://apisicul.com/userfiles/files/31739030489.pdf
    • http://chunmianxian.com/upfolder/e/files/20210903150012.pdf
    • http://art-wonders.com/ckeditor/ckfinder/core/connector/php/uploads/files/xelavudilikofidunugizazom.pdf
    • https://textolinguisticsolutions.com/upload/editor/file/37196325879.pdf
    • https://www.terraton.com.my/ckfinder/userfiles/files/51000982253.pdf
    • https://songhong-thudo.com/img/files/13485536265.pdf
    • http://bridgestone-ice-cruiser-7000.ru/ckfinder/userfiles/files/28909668856.pdf
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb8b8422f5---32730617842.pdf
    • http://fibertechnique.com/tmp/file/zizavigusasasinawakajul.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/0tcob4ekis9lpbk2a8jqs788n4/80358272061.pdf
    • http://cp-1.ru/userfiles/files/23462884016.pdf
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/5u8jg9f40ngl7onqlbgtbcltqn/wopawunuxewezekezed.pdf
    • http://zge-led.com/luodan/images/userfiles/file/xuvobufemetuw.pdf
    • https://bankubezpieczen.pl/userfiles/file/56303166167.pdf
    • https://hasekei.jp/userfiles/file/87457358979.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_off0000b116.bin
f3858ea45db2eddec15468ed134d0d3d91cc28a16d14efa05b8cfeb63cc69ca3
pdf-font-stream PDF embedded font (sfnt) at offset 0xB116 10616 bytes
font_01_sfnt_off0000c92c.bin
d08f75613c7c4aee725ec0246556af06668127d29179163b3386c0dc253993a0
pdf-font-stream PDF embedded font (sfnt) at offset 0xC92C 17632 bytes
font_02_sfnt_off0000f666.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF666 16792 bytes