Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4a2b687a8ad5096…

MALICIOUS

PDF

88.8 KB Created: 2021-06-25 23:16:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a947aa0f931344373845ad3689f6d025 SHA-1: 6321f8dcf1c4e1617332321d6caeda793dcb5a23 SHA-256: f4a2b687a8ad5096ece80ab431a6907ccb7a72f0988c5433df7c62919fc31132
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan. Static analysis revealed it contains a link farm pointing to compromised WordPress upload storage and other disposable hosting sites. The ML classifier also strongly indicated maliciousness. The primary attack pattern involves directing users to potentially malicious external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://clumba-indoor.ru/files/files/diwuvapusawolil.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d548010fec9---foseluruwuwuwones.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/4db347d89f47a9ec00645e169250277d/gejutekifekuzisiwepowiw.pdf
    • http://deckdreams.ca/clients/3/34/34055ef41782f8f15ebf372c1e39ecad/File/denarameje.pdf
    • http://terralindahigh1981.com/clients/866868/File/tesobokesudigisezaluja.pdf
    • https://vestol.bg/files/file/20171609213.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c47fbec6a90---68599408699.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160be0319496dd---60942914854.pdf
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/8a1873eca8a278de9229857b2ff6f261/kisokotidew.pdf
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160b98a496dfd3---ziwufukapo.pdf
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/eedb57a3f1d79f7e842961451368b1ba/vejajiri.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c6e29d8752e---13024623791.pdf
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/8fe03ad734c4b3a9ce7da1fdf0375a0c/lagigivipuzo.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/mr96v69qn4ukbdnc8j6o3a58n5/vekuxuve.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608c2a414322d---66041947552.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca2b23247af---88081222196.pdf
    • https://angkoronetour.com/userfiles/file/vavevunozasafepu.pdf
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/c9ieu1l0omn0h12s8u6u3e7fkl/78893807781.pdf
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160861f0ec31c4---19654437500.pdf
    • http://robwalker.net/fckupload/file/rowesototixaloxum.pdf
    • http://10glazsikeyrosa.ru/file/toxizexovuguvo.pdf
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7aeab0f76e---talolajodisabag.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=schuylkill+county+towns
    • 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_off0000f9e0.bin
1467adb1fb397f14ecb85e9a2b5a9c89a70ba59c5b0a7a3520bb76c220582082
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E0 10400 bytes
font_01_sfnt_off00011164.bin
bce2f2c184e0c815950a9521c62a216df06163f37d7bd439945e6d76728e94d8
pdf-font-stream PDF embedded font (sfnt) at offset 0x11164 17588 bytes
font_02_sfnt_off00013e50.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E50 16792 bytes