Malicious PDF — malware analysis report

Static analysis result for SHA-256 bff758541bdc8939…

MALICIOUS

PDF

83.1 KB Created: 2021-07-15 16:58:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3ff313f1cd559e0b0821be2f2e8be1ad SHA-1: 556a050a119bbc8236a5e61daa95e768d39a1999 SHA-256: bff758541bdc8939d946eaff19f73780a1fe0dd15291c74ec47f5b1afe1ee23e
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm, with many URLs pointing to compromised WordPress sites. The ML classifier and ClamAV also identified it as malicious. The primary purpose appears to be directing users to potentially malicious content hosted on these compromised sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/ba5sjqksacvgmemh4icdq8faoe/35396224897.pdf In PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d963459213---90507734133.pdfIn PDF document text
    • https://limsurdua.com/contents//files/25072269315.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab27dd0c94a---88392144019.pdfIn PDF document text
    • http://cdmvt.cz/sites/default/files/89448954220.pdfIn PDF document text
    • http://s2ipower.com/survey/userfiles/files/bapoxubafulomexexag.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd28c062b0---84232957147.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a40db1c5a2b---13041771834.pdfIn PDF document text
    • http://phuwangnam.com/user_file/file/fonivodiduduwemivapupi.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160be98b5db1cc---86418895739.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/38532859908.pdfIn PDF document text
    • https://sasalidayanisma.org/uploads/file/sototufiwe.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/vimawewiduj.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/499ee027f1453a43b85076bd411568ad/15669539873.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/6simrjfcnpid019dgjs58b4qso/batebevotukikojuzan.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1607c7ea976747---lujepinifo.pdfIn PDF document text
    • http://cpgny.com/userfiles/files/zagetefedijir.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608de10bf1704---wugijidasukibafovisumuk.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/82hl1cnbqqa78celiq1elbkvi0/94374689654.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160c63933798e3---52322543551.pdfIn PDF document text
    • https://resulgame.com/calisma2/files/uploads/mewotiku.pdfIn PDF document text
    • https://dnmpaint.com/sdcc/images/file/31929513053.pdfIn PDF document text
    • http://szkolka-wiercioch.pl/files/file/77767489120.pdfIn PDF document text
    • https://evpersoneli.net/ev-personeli/file/zezijujexoponesepi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=1+cup+in+millilitersPDF 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_off0000e4cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4CB 16752 bytes
SHA-256: eba8f687999a9ddae3f36c600b56088c0982f1b5016d5c2ef7a1bbe20bd8decd
font_01_sfnt_off0001104b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1104B 10308 bytes
SHA-256: 6c7e5587f93b5c64f6fc1d0408eb51cda2b5a9b618e031cad05b1b88bf3ee012
font_02_sfnt_off0001277f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1277F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1