Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbc88397854b6559…

MALICIOUS

PDF

88.6 KB Created: 2021-06-29 14:58:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a2180ffee65d23b78fd7d49b2793252e SHA-1: 253e6fd87f4b1f5526a617b4cc3b0ec16e0c665c SHA-256: fbc88397854b6559b5397eba9ea832c6d4de0b60e86838b21b7d86d31bddcbe5
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, suggesting a link farm designed to host malicious payloads. The presence of a link with the UTM term 'unable to view pdf on android' is a common lure for phishing or malware distribution. ClamAV detection and ML classification confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/16081901ddc0a8---tuzijizajirudevipujax.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/9gbl7ha1oveat3t7rt54t3fbb4/59338469415.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/602a3c07aaeb45ca928923c9ed85a61c/69274488265.pdf
    • http://wallsfamily1912.com/clients/876683/File/81837466130.pdf
    • http://skisun.it/userfiles/files/47094217084.pdf
    • http://baigeleather.com/userfiles/file/14589090717.pdf
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d0aa1c0e3a0---waruwivuvaninunaxik.pdf
    • https://amenajarisiconstructii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160892ad4d2af2---pakekolupow.pdf
    • http://ainut.fi/userfiles/file/9207147980.pdf
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/e08bce7a7bc0409f2e270626106e9311/lolamujivex.pdf
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/f4542e70bd3c19a32c8cd2c5714acd1c/41779367077.pdf
    • https://economiadecomunion.com/ckfinder/userfiles/files/fisirorojoturokadirinub.pdf
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/87e28081879624683899e41f5cad10e8/lupibixojefupajomem.pdf
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/765c47d7e8c2a47abd4f8acaa983baea/rizapinoxebusomarobogeza.pdf
    • http://naturallabs.fr/userfiles/file/nulovapigevupi.pdf
    • https://chmelo.hu/sites/default/files/file/46411800339.pdf
    • http://www.urbanwaterways.info/files/mumip.pdf
    • http://billsky.ee/files/file/wegiwarufugoximesuxebaj.pdf
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/atr41k2dhugl64ivvtfgmebad1/fipodutofarid.pdf
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb8789be0fd---9624869200.pdf
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a59282cde92---dusulisamowiwena.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2ebddcfd0---30172390517.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160a15db1688a7---bebemirirak.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=unable+to+view+pdf+on+android
    • 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_off0000f5e9.bin
859bb63bf09535c679c68df717ff074ff66dce0b2e421e7e0aa2e003497f048c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E9 10620 bytes
font_01_sfnt_off00010e1b.bin
f0149db10e0722476f2e13fcec39e2f6aa8b7a0c1d68c6cad85fcd4964ff2d53
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E1B 17908 bytes
font_02_sfnt_off00013d3f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13D3F 16792 bytes