Malicious PDF — malware analysis report

Static analysis result for SHA-256 baffc88cffed71c1…

MALICIOUS

PDF

73.6 KB Created: 2021-06-28 19:45:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 203e1672a50bf1cfd03c2cf82f8a46a5 SHA-1: b5dcc90833e87eae950069e61cf47261309d7b3c SHA-256: baffc88cffed71c1995c7f27765ee618103b3a71cea06ac2fe1f773ec3ae4c37
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous external links, many pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further indicating a non-legitimate purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://philabc.ru/uplcv?utm_term=comparative+and+superlative+exercises+with+answers
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160963569ce58d---bitobojot.pdf
    • https://leosservices.com/userfiles/file/4716047836.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160899c076c010---33105629110.pdf
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076bf5a9f707---51343036473.pdf
    • http://dakmet.pl/upload/50772730534.pdf
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/12c3583c644d42cadb4e77e58c18e310/74482805677.pdf
    • http://kapli74.ru/upload_picture/76718756486.pdf
    • http://piau-po21inn.com/CKEdit/upload/files/gotelilanudojazinos.pdf
    • https://activepymes.com/pub/file/13843085420.pdf
    • http://kcde.kr/userfiles/file/lurun.pdf
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/cd2bfe5f8ad7b3d9171983924abef0c8/96577726791.pdf
    • http://humanitool.ru/userfiles/file/43457588977.pdf
    • http://abpaluso.com/upload/file/rabog.pdf
    • https://www.visitrwanda.com/wp-content/plugins/super-forms/uploads/php/files/f7e28e823dc0b98216ed741f0c3d5acf/volavigukasenukigelu.pdf
    • https://www.harasportcenter.com/wp-content/plugins/super-forms/uploads/php/files/pmb1rut57j3t6ioe0gbg3ofnau/xudekaxumat.pdf
    • http://ahdongjiu.com/upload_fck/file/2021-4-29/20210429171439950286.pdf
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080a5f3bc330---penixuvojipitogurajopaf.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609833fdcd27d---rirovasimijaxoziw.pdf
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/160ac4c410ee01---geruvu.pdf
    • https://www.tanyadantus.com/wp-content/plugins/super-forms/uploads/php/files/33eb9203c8d60d32e8dd546198708043/17430790316.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c6deac22b65---kipenofalibadakov.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c15baa63618---75969942628.pdf
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c962cd51d46---lelovoxom.pdf
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/3a583191c24ad0c1274e09fd6ff52ad7/163945547.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_off0000bfd1.bin
73066d09c5037929ce533ed66a94a5693f684d560cbff2ae63b8f80294fd6ddf
pdf-font-stream PDF embedded font (sfnt) at offset 0xBFD1 11164 bytes
font_01_sfnt_off0000d9cd.bin
edaf76c3a5559f4613e41075d5bc477fdcebc524a589a1fb66f06ff9e30c533b
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CD 15300 bytes
font_02_sfnt_off000100e3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x100E3 16792 bytes