Malicious PDF — malware analysis report

Static analysis result for SHA-256 5bd41af3918471aa…

MALICIOUS

PDF

80.4 KB Created: 2021-09-19 11:01:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: ad99b3896351f80e6f37334d08676306 SHA-1: 08caf1ee4864be58f738e021f30d59a1a17d29da SHA-256: 5bd41af3918471aabfa616c5fa48bb97d4fa4cb88b876a3f4d12b487cc59a30a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS uploads or disposable domains. The embedded URLs suggest an attempt to trick users into downloading further malicious content or visiting phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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.
  • 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://spiregene.com/image/files/20210917_182314.pdf In PDF document text
    • http://pravkniga.ru/files/userfiles/files/mukafinugenetotilorazelus.pdfIn PDF document text
    • https://drrajanmahtani.com/userfiles/files/sexabosokosanesarenuk.pdfIn PDF document text
    • http://theseadiaries.com/ckfinder/userfiles/files/kazatesizigidawijapomafu.pdfIn PDF document text
    • http://live-lessons.net/lcj/web/uploads/assets/file/77298357181.pdfIn PDF document text
    • http://sunmoon-glory.com/web/upload/files/katumex.pdfIn PDF document text
    • http://weighlessthisyear.com/ckfinder/userfiles/files/58349630892.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6abb50a73---47276211876.pdfIn PDF document text
    • http://usairsprings.com/userfiles/file/9808283817.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/16132404311d97---55482379775.pdfIn PDF document text
    • https://cursosadistanciayonline.com/medios/files/gedejusakesejuj.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/m1275fg7jqc74kkektv5g0eq7p/mikujakukufububunedofipen.pdfIn PDF document text
    • http://borik.customreal.sk/data/files/35876975530.pdfIn PDF document text
    • http://milkexim.ru/imgeditor/file/vamudipifenigejuxaxa.pdfIn PDF document text
    • https://techinnsrl.com/writable/public/userfiles/file/74065660715.pdfIn PDF document text
    • https://pre-www.bridge-academy.com/uploaded/ckeditor/files/xuwodimefaxolet.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/73340256913.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/96cc0aa52ed077362d28c95e86e976c5/46111103740.pdfIn PDF document text
    • http://monterroso-construpuntos.com/campannas/file/84199975612.pdfIn PDF document text
    • http://rallyteamwalraven.nl/file/61599106743.pdfIn PDF document text
    • http://centromedicoveterinarioadda.com/userfiles/files/19262665891.pdfIn PDF document text
    • https://pre-www.bridge-academy.com/uploaded/ckeditor/files/dejukavig.pdfIn PDF document text
    • http://mikailang.com/userfiles/file/20210913164735_1771077039.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=download+at+the+app+storePDF link annotation
    • 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_off0000d6da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6DA 10484 bytes
SHA-256: ebb09ed00c6ee8da6cd0b114ab71d1717de2c97c3daa90942f99484e4d42677e
font_01_sfnt_off0000eeac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEAC 17596 bytes
SHA-256: f0379a425e081eebdbc1764622568193605b9e50d8017b3d18b7a0bfb31c9b1d
font_02_sfnt_off00011bb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1