Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5fca7f1f31bfcbc…

MALICIOUS

PDF

83.0 KB Created: 2021-06-28 08:03:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 74414fb4fdbe99a153c0009778d9a744 SHA-1: db30684cf654408f7f4274e183ab5d075649d769 SHA-256: b5fca7f1f31bfcbc4af8eb341300c12e86530bdf69f2a86ae75c6864a0bbaece
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised CMS upload storage locations, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, but the presence of numerous external URIs and the heuristic firings confirm the attack pattern.

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://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/f39f94d8e720b719516d2dfba3f86736/wuterekixikawupavipiboxew.pdf
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/uegijcm3offh1j79v6qau8qvet/kosemerulu.pdf
    • http://kasargod.net/uploads/file/48036849617.pdf
    • http://aarogyamedico.com/userfiles/file/65472987092.pdf
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/a47903fa7862d8e6b9af7a9951ec3da4/27883070020.pdf
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae4c6e24ada---70951436819.pdf
    • http://www.specemc.ru/upload/files/92336712178.pdf
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8d5a086f4---wedomiserutorem.pdf
    • http://nanoscopy.ru/uploads/files/nukexopodolijoj.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160780e1213245---65000717099.pdf
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/ff3903ad770850be04546f2d62ae1c0a/60067511494.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd75a64d10---widamekisuzewawagowaja.pdf
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d9456a5a45---83753321927.pdf
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d561932ba4---99729216122.pdf
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce1e67c6da---35512285112.pdf
    • http://nuitsdartistes.eu/images/file/pufakewefotu.pdf
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/g58024maij7f6m4e85q6erdhne/favaxonamu.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16095ef09d8eee---vudetunevawebelumivi.pdf
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/069d85950f897deab6615826f86ef3a1/mufiwamixik.pdf
    • http://bahtiyardishekimi.com/fckfiles/file/43550415193.pdf
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cc8ad930949---48940604813.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160acc098b61ec---rolekezomodifukujejafel.pdf
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/0288ac6a2ecace44191c3ff02b4d6aa3/deralot.pdf
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/b91e4e354bc31ed97e37a1af3104c632/77419368024.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=what+is+homogeneous+mixture+and+example
    • 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_off0000e251.bin
b7bec4fb4d331e8d54fb79aff4332600754ea567dec3bb0714871265ef904efe
pdf-font-stream PDF embedded font (sfnt) at offset 0xE251 11032 bytes
font_01_sfnt_off0000fba3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBA3 16792 bytes
font_02_sfnt_off000113b5.bin
5754916c256b003e676595e1234789d4894c608a85f760710b2f645566216df7
pdf-font-stream PDF embedded font (sfnt) at offset 0x113B5 16520 bytes