Malicious PDF — malware analysis report

Static analysis result for SHA-256 cff0038632d01f7d…

MALICIOUS

PDF

74.9 KB Created: 2021-09-06 11:58:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e2be43536539fa9d16efd8a93e8b61d4 SHA-1: 53edcfc4709981481868f0b3fc2a819470557e76 SHA-256: cff0038632d01f7da37fdb25d7b01031a147caaa0e0a4fbb0198e1db56f87dd2
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with many URLs pointing to potentially compromised WordPress upload directories or disposable hosting. These findings suggest the document's primary purpose is to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://euro-ex.net/images/blog//file/88188369131.pdf
    • https://www.thaiahpa.com/flash/files/25014330015.pdf
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609e2b635d22c---74014982668.pdf
    • https://cooperspick.com/files/vofawinonalewatitotar.pdf
    • http://dolupin.com/calisma2/files/uploads/xusimamerizanoru.pdf
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160961d054e5d3---kuluvewefiv.pdf
    • https://classconnbio.com/img-jacson/files/23168776710.pdf
    • http://sakuragiramenandsushi.com/uploads/files/sowaparulujuj.pdf
    • https://webvitamin.vn/app/webroot/uploads/files/gizaj.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081ac9499970---zofekesi.pdf
    • http://ccymgr.com/clients/a/ab/abc9983c1712fd324c9320bcfcf975a8/File/kuvemitu.pdf
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/0e5668c7c809b67139d986cb66293fee/72113264866.pdf
    • http://nfc.soo.jp/file/336400930.pdf
    • https://www.gurkhasfinance.com.np/ckfinder/userfiles/files/8680430343.pdf
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1607b19cf44dc3---5680689267.pdf
    • http://randalljroutson.com/clients/44711/File/gopusuruwotovafi.pdf
    • http://riverbendhay.com/clients/4/4e/4e1cbd84181290ddb66fb035c9950ff6/File/91055078417.pdf
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/23696ff61a8d071523cb32dd0045a2cb/fuwepitojetum.pdf
    • https://talaa-obour.com/webmisr/uploadwebmisr/file/tizivepepezuju.pdf
    • http://www.climatisur.com/ckfinder/userfiles/files/bugewikujo.pdf
    • http://bestbuyfromindia.com/userfiles/file/gidesatalabiti.pdf
    • https://lapalettedesarts.fr/gestion/file/batovini.pdf
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a32dbb032c---4337782670.pdf
    • https://davaocarrental.com/images/file/21528377231.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=surah+rahman+online+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_off0000c150.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC150 16792 bytes
font_01_sfnt_off0000d967.bin
ecf81e941d9dde795761a7777a105a6875af02087a59068b1d0482ec6366fb06
pdf-font-stream PDF embedded font (sfnt) at offset 0xD967 10672 bytes
font_02_sfnt_off0000f188.bin
39439a889402ae0de0ce82b9d4b085b7c5e2c4c5f6053689c38429142fec8a3f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF188 17160 bytes