Malicious PDF — malware analysis report

Static analysis result for SHA-256 20b502f5b7e52a6e…

MALICIOUS

PDF

79.8 KB Created: 2021-07-26 18:53:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 949971548cb734ed8013fba56f992ef9 SHA-1: 40dd01a654d438c22443fa18b4724b6c36789be0 SHA-256: 20b502f5b7e52a6e1fba737f9377b3421133db10eb6484ed2124e632c8b8bfdf
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely involving exploitation of PDF vulnerabilities to redirect the user. No scripts were extracted, but the heuristic firings point to a malicious document designed for initial access via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 http://viral-list-machine.com/ckfinder/userfiles/publics/files/28349265547.pdf
    • https://sanmuabancongty.vn/images/content/files/setibeze.pdf
    • http://autoshiftbid.com/fckeditor/userfiles/file/82471395813.pdf
    • http://purifoy2020.com/clients/1/11/118d8b7ee1ea4bab8fb19da95c56260f/File/fazuzaxebesax.pdf
    • https://bajrahrs.com/userfiles/file/gomekarimumedo.pdf
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f49856830a2---gaboxim.pdf
    • https://ludifrance.fr/userfiles/file/ginogulogafijarajus.pdf
    • http://modnyi-buket.ru/uploads/files/29009846025.pdf
    • http://rdasesores.gestconcursal.com/editor/ckfinder/userfiles/files/deluwudilexu.pdf
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/4c60d05e8f547c4fc478ffcac6b8d3c5/gozuvabidunonolugewudetup.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/a7665a7b14a7ccee8050080216048fe4/pejenewijonagekapim.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/5c34f1a6f47eb06455ae10e1c4ed612f/goboripigixutifop.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/1j96vqpjhuvq25rd81shab6hib/68415520818.pdf
    • https://alianzatours.com/imagenes/file/35260892751.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d14964e236---86805347727.pdf
    • http://www.biotanika.pl/upload/file/bozevulegojonufeloxaz.pdf
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f24037f1c6---84324295753.pdf
    • https://corpusbg.com/files/fck/file/90996302819.pdf
    • http://greathorserider.com/ckfinder/userfiles/files/87574009934.pdf
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/o6u1tb6uc45im53i3j9m0t1gc0/zunerikosifixamatezad.pdf
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/a14574lhauia7q064n68hsoud7/37943707282.pdf
    • http://testplanet.nl/uploads/files/naregepifisigekuxu.pdf
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/40211097008.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=ib+diploma+biology+textbook+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_off0000d517.bin
9752c628609765021566c7bc3f6c48e44bafb3396f04a698bc20f9a2c201e68e
pdf-font-stream PDF embedded font (sfnt) at offset 0xD517 16560 bytes
font_01_sfnt_off0000ff9b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF9B 16792 bytes
font_02_sfnt_off000117b2.bin
e137872abb1e6eb00ba7b1bafafa03e359d91c71de6358035130fb524ee292dc
pdf-font-stream PDF embedded font (sfnt) at offset 0x117B2 10868 bytes