Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c4949256fed5886…

MALICIOUS

PDF

94.3 KB Created: 2021-07-25 13:53:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: b5fb985d5934089c79a3075b1d1a7995 SHA-1: 350228d6ce595ec44413a9c3b8669afc42d7f34e SHA-256: 8c4949256fed5886d731c6fd63dba39c8bf4bf88dc391dfc13b8db3e455660eb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous URLs pointing to potentially compromised or disposable hosting, characteristic of a link farm used to distribute phishing content or malware. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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 https://aimtronu.org/userfiles/file/53908639983.pdf In PDF document text
    • http://caryhigh1987.com/clients/41333/File/rilepuwipukubelalal.pdfIn PDF document text
    • http://classofjoy.com/KK/userfiles/files/dozerizedifevenawikenoju.pdfIn PDF document text
    • http://medicapoland.pl/uploaded/file/90060529814.pdfIn PDF document text
    • https://gegeny.hu/uploads/file/doxebigidovazeroko.pdfIn PDF document text
    • http://njuhome.pl/ckfinder/userfiles/files/gefokujedudezilup.pdfIn PDF document text
    • http://erictex.com/ufiles/files/pusisawadesejatesarasixo.pdfIn PDF document text
    • http://flatadministration.com/uploades/fckeditorfile/tivetasojirajepalojim.pdfIn PDF document text
    • https://annekienlen.fr/imagesfile/tokisalu.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/6f568724b5cf892749d6b06318b30b99/37454554351.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/p3f9nf5h9bscogkmmtmfjl6834/51952848704.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/ed1f949a1bbe9d9ae5af1337fa7e3ded/73619784311.pdfIn PDF document text
    • http://candientuvibra.com/images/file/tazogerixedelab.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1eae20961---32777459969.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160afd639d18e1---86645432592.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160fcbd718f877---lemexititokogebodak.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/59006492080.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/5aa7df94129b585b2fa871a46ad93567/40458319110.pdfIn PDF document text
    • http://aahsclassof1978.com/clients/b/b6/b6117739535924054831d33ecd54b00a/File/lujukizunevumedab.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/jidovesokudumifuwaxov.pdfIn PDF document text
    • http://yoron.net/up/files/84040048328.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=what+did+ancient+egyptian+farmers+do+during+flood+seasonPDF 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://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_off00010f64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F64 11272 bytes
SHA-256: 8b828b2c4b1a2b08e6205ec0b3c5ba57ee6cd8f0d68016d0ed89a093d8be3bb8
font_01_sfnt_off00012977.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12977 16476 bytes
SHA-256: 45d1ca4985980609fd3aba61d44b9bd45867c07b1b1d72bd45b2e7005bb87fcd
font_02_sfnt_off00015446.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15446 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1